Combine 2 Tbsp each of molasses, ketchup, honey, maple syrup and all seasoning in a medium bowl. Place chicken in a separate bowl.
Add about 1/4 cup of liquid mixture to the chicken and stir to coat well. Place chicken and the sauce it was in on top of vegetables. Place butter on top of chicken.
Bake for 25 minutes. Meanwhile, heat remaining sauce in a saucepan and bring to a simmer. Combine cornstarch and water in a small bowl.
Add cornstarch slurry to sauce and stirring constantly bring to a boil, then reduce to a simmer.
Add this thickened sauce to the top of the chicken and continue to bake for another 20-25 minutes, or until the chicken is cooked through. You might need to remove the chicken so it doesn’t overcook, yet continue to bake the vegetables until they’re done.