This healthy chocolate oatmeal cake recipe uses old-fashioned leftover oatmeal instead of flour. A brown sugar or cream cheese frosting makes it dessert!
We all know that eating leftovers is a great way to save money, right? But sometimes eating leftovers is just boring.
Or unappetizing… like the case of leftover oatmeal.
I recently learned how to make leftover oatmeal cakes – thick slices of oatmeal that are pan-fried in butter and drizzled with syrup. They’re crispy on the outside, soft on the inside and so delicious you never would have thought leftover oatmeal could taste so good.
Why Make Leftover Oatmeal Cake
Hold on to your hats friends, your oatmeal making days are about to multiply because this cake is AMAZING.
I know that sounds weird, by the way… that leftover oatmeal tastes amazing. But really, it does!
I had to restrain myself from licking my fingers and forks and plates and picking at crumbs while taking the photos for this blog post because OH MY GOODNESS, this chocolate leftover oatmeal cake is like cake meets brownie meets there’s no way there’s leftover oatmeal in this because it’s too stinkin’ good!
Yep. That about sums it up.
As I was working on this new healthier version of an old recipe, I realized that our eating habits have changed just slightly for the better.
First, we avoid granulated sugar as much as possible as we continue to quit sugar. Instead, we use honey and maple syrup instead to sweeten.
It works in almost all of my baking… peanut butter chocolate chip muffins and strawberry lemonade donuts and banana nut muffins with crumb topping and pumpkin donuts and zucchini carrot apple muffins.
I’ve learned that unless you’re truly making a cake – like you would with homemade yellow cake mix or homemade chocolate cake mix – you can get away without using granulated sugar.
Second, we’re re-committed to using whole wheat flours in our baking and eliminating all-purpose flour. We don’t do a ton of baking since we did the Whole30, but when we do, I want to make sure that it’s whole grain flours.
Third, I’ve streamlined my efforts so that I don’t have to work as hard in the kitchen. That means delicious recipes with less work and less dishes. YAY!
Chocolate Leftover Oatmeal Cake Ingredients
- melted coconut oil (or melted butter)
- maple syrup
- yogurt (or buttermilk)
- egg (or flax egg)
- vanilla extract
- extra thick leftover oatmeal (not runny)*
- whole wheat flour (or all-purpose)
- baking soda
- cocoa powder
- chocolate chips
Notes on Ingredients for Oats Chocolate Cake
- Keyword, LEFTOVER. I don’t recommend making fresh oatmeal just to make this recipe. Fresh oatmeal tends to be soupy and the texture isn’t consistent. Leftover oatmeal is crazy thick, and that’s what you want for this recipe.
- With that said, there is a hack you can do if you absolutely cannot wait to make chocolate leftover oatmeal cake and you don’t have leftover oatmeal: make oatmeal as you normally would, and then add oat flour. I recommend adding 2 tablespoons at a time until your oatmeal is very, very, very thick.
- To save time, here’s how to make Instant Pot Oatmeal and oatmeal in a slow cooker.
As I mentioned before, I used honey and maple syrup to sweeten this chocolate leftover oatmeal cake. You can use one or the other, or both. I like to use both because then neither flavor really stands out in the end.
- Again as I mentioned, I used white whole wheat flour. You can use red whole wheat flour, all-purpose flour or even a gluten-free blend if you’re sensitive or allergic to gluten.
- I would not recommend using almond flour or coconut flour in this recipe because of how those flour work in baked goods.
How to Make Oatmeal Cake Step By Step
Step 1. Preheat the oven to 350F. Grease and flour an 8×8 or 9×9 square baking dish. Set aside.
Step 2. Combine wet ingredients – coconut oil, honey, maple syrup, yogurt, egg and vanilla extract – in a large bowl and whisk well to combine.
Step 3. Add leftover oatmeal and whisk well to combine.
Step 4. Add the remaining dry ingredients and chocolate chips and stir well. The batter will be thick.
Step 5. Pour into the prepared baking dish and use a spatula to make the surface mostly smooth.
Step 6. Bake for 25-30 minutes, or until a toothpick or knife inserted into the middle comes out mostly clean.
- You can make thin leftover oatmeal thicker by adding oat flour. Add 2 tablespoons at a time until the oatmeal is so think you’d have to bite into it and chew it.
- I like to bake mine for 25 minutes for a gooier cake, similar to a brownie. If you want a more cake-like texture, bake for 30 minutes.
You can make this delicious leftover oatmeal cake recipe! It’s healthy, easy and budget friendly.
Leftover oatmeal is delicious in this chocolate oatmeal cake. It’s a great way to use up leftover oatmeal, saves money and avoids waste.
You can follow these step by step instructions and use leftover porridge to make a delicious leftover porridge cake.
More Money Saving Dessert Recipes
- Chocolate Chip Banana Ice Cream
- Chocolate Peanut Butter Fudge
- Homemade Peanut Butter Cups
- Avocado Chocolate Mousse
- Chocolate Peanut Butter Cake
Loving LeftoversLove meal planning but hate leftovers? Download my free eBook Loving Leftovers and learn how to save money by turning leftovers into recipes your family will love!
Chocolate Leftover Oatmeal Cake
This healthy chocolate oatmeal cake recipe uses old fashioned leftover oatmeal instead of flour. A brown sugar or cream cheese frosting makes it dessert!
- Prep Time: 10 mins
- Cook Time: 25 mins
- Total Time: 35 mins
- Yield: 9 1x
- Category: Dessert
- Method: Oven
- Cuisine: American
- 1/2 cup melted coconut oil (or melted butter)
- 1/4 cup honey
- 1/4 cup maple syrup
- 1/4 cup yogurt (or buttermilk)
- 1 egg (or flax egg)
- 1 tsp vanilla extract
- 1 cup extra thick leftover oatmeal (not runny)*
- 1 cup whole wheat flour (or all-purpose)
- 1/2 tsp salt
- 1/2 tsp baking soda
- 3 Tbsp cocoa powder
- 1/4 cup chocolate chips
- Preheat the oven to 350F. Grease and flour an 8×8 or 9×9 square baking dish. Set aside.
- Combine wet ingredients – coconut oil, honey, maple syrup, yogurt, egg and vanilla extract – in a large bowl and whisk well to combine.
- Add leftover oatmeal and whisk well to combine.
- Add the remaining dry ingredients and chocolate chips and stir well. The batter will be thick.
- Pour into the prepared baking dish and use a spatula to make the surface mostly smooth.
- Bake for 25-30 minutes**, or until a toothpick or knife inserted into the middle comes out mostly clean.
* You can make thin leftover oatmeal thicker by adding oat flour. Add 2 tablespoons at a time until the oatmeal is so think you’d have to bite into it and chew it.
** I like to bake mine for 25 minutes for a gooier cake, similar to a brownie. If you want a more cake-like texture, bake for 30 minutes.
- Serving Size: 1 slice with icing
- Calories: 400
Found this recipe while travelling in our caravan around South Australia. Had leftover porridge, cream that needed using that I made into buttermilk(ish) and honey that I needed to use before we headed into Western Australia. Perfect. And it was perfect. Yumm
My husband also tested positive for Covid so we are isolating in our van!!
Sure brightened up our day xx
Karen @ Team Crumbs
Thank you for sharing, Lynne!!!
Great recipe. I used 2T oil and 80 grams of very ripe banana. Did not use sour cream. Added 1tsp vinegar. Used Hershey chocolate syrup instead of the honey and maple syrup. Great texture. Baked as cupcakes about 22 minutes.
Love it! Not too sweet and super moist, with a very pleasing crumb. Perfect for my leftover steel cut oats.
question – have you ever doubled the recipe? If so, what size pan did you use?
I’m wanting to make this cake, with icing for a party of 14.
SJ - Team Crumbs
You can mix the ingredients together the same doubles but we recommend using 2 8×8 or 9×9 dishes. It may not bake evenly in another sized pan. 🙂
I love this recipe, we make it all the time, but I did a variation- Peanut Butter Banana! I added peanut flour for the cocoa and subbed a banana for half the oil and it turned out great. Thanks for all the awesomeness going on over here at DWTC!
Made this into a pumpkin chocolate chip cake! Subbed yogurt and 1/2 the oil for 1/2 cup canned pumpkin, changed the 3 TBSP cocoa to flour and added 1/2 tsp pumpkin pie spice and 1/2 tsp cinnamon. So great, thanks again for the recipe!
Based on your comment I reduced the oil to 2T and the rest banana. Worked well
Could you use Einkorn flour? I’m not a fan of regular wheat.
I was searching for recipes that used leftover porridge and found so many uses for it! Love this recipe and it freezes well. I cut up into even smaller slices and froze most of it. It’s delicious to grab a slice then zap in microwave for 20-25 seconds it reminds me of self saucing pudding as it’s warm and gooey. The texture is amazing and I will always make chocolate cake this way now. So damn good.. 🙂
Came out amazing. I doubled the recipe, used melted butter, and milk that was going sour instead of buttermilk. I bake with whole wheat flour a lot lately and one big tip I learned is to let the batter sit for a while before baking it. The whole wheat takes longer to soak up the moisture, so I always put everything together first and then set the oven to preheat. That usually gives the batter enough time. I also always end up adding more milk to my batter. It’s always way crazy thick when I follow these kinds of recipes, but I add in extra milk (in this case, the sour milk) till it’s more the usual consistency and it comes out great. Not to mention saves my arms in the stirring. Thrilled to find this recipe!
Really lovely cake, we had cinnamon in the porridge too and I used coconut oil instead of butter and it was delicious. Just like a brownie, but better as only good ingredients in it! Thanks.
You’re very welcome, Katherine!
This was delicious. My eight, three, one year olds loved it. I didn’t have yogurt or buttermilk so I Substituted it for with avocado.
Ooh, great substitution idea, Laura! I’m so glad your kids loved it! ♥
Great minds think alike 🙂 My flavors were a bit off on last creative oatmeal and wanted to change up leftovers for my girls after 2 mornings of it. So chocolate makes most things better, added some egg, baking powder…and fed them cake for breakfast 😉
Happened upon this recipe when searching for ideas to use my leftover oatmeal, made from steel-cut (Irish) oats. Used a chia seed “egg”, coconut oil, dark chocolate baking bits, yogurt, and 50/50 graham wheat/all-purpose flour, but I’m convinced any of the options given would be equally satisfying. Texture was light but moist, with the flavor of a dense brownie, and “nutty” – I believe from the oatmeal. Was deliciously addicting; decadent but not sinfully so. It took great discipline to not eat the entire pan right out of the oven. I highly recommend slightly warming leftovers for a few seconds in the microwave before eating, as the warmth brings out the chocolate flavor beautifully and makes it a “melt in your mouth” experience. Though not needed, a spot of whipped cream or small scoop of vanilla or mint ice cream on the warm cake would class it up beautifully.
Oh Karen, mint ice cream or whipped cream?! You just took leftover oatmeal and made a decadent DESSERT!! ♥
Made this last night. My leftover oatmeal had cinnamon and raisins already stirred in from the morning’s breakfast, so raisins and all went in. The cake turned out ridiculously delicious and moist! Asked my hubby his opinion before I revealed the secret ingredient. He loved it! Might have to make a double batch of oatmeal tomorrow morning specifically to have leftovers for another cake. Super good and we can tell ourselves, with the inclusion of oatmeal, that it’s “healthy!”
I love that you added the leftover oatmeal, spices and raisins and all! I bet that made for a delicious cake, and high fives for the husband loving it too!!
I used coconut oil but when the egg, maple syrup and buttermilk were added, the oil hardened. I am having a terrible time getting this to loosen up. I don’t want to throw all this out.
It shouldn’t make too much of a difference in the end Judith. Mix it as best as you can and bake. Next time, make sure your ingredients are room temperature and add the coconut oil last. That will help slow the hardening of the oil!
Whoops! Think I posted this here instead of on oatmeal recipe-sorry…
No worries! Glad you liked it Kimmy!
I just made this in my 2 qt electric pressure cooker & it turned out awesome!! Didn’t have to add milk, it was naturally creamy. My hubby, Mr Picky, loved it too! We really like oatmeal but don’t have it much cuz i hate having to stand there & stir. I told hubby were going to be eating a lot more oatmeal this winter!! Lol…
Just wanted to tell you how much I love this recipe! I make it at least once a week, usually before bed so we can have it in the morning. I use my own gluten free flour blend and like to switch things up. Recently I added fresh cranberries along with the dark chocolate- yum! I have another batch in the oven with mashed banana, pecans, and chocolate chips. Since we’re a family of six we typically polish off the whole pan; I’ve been known to double the recipe.