Spray a 9 x 13-inch baking dish with cooking spray and set aside.
In a large bowl, beat together Bisquick, eggs, and milk. Stir in remaining ingredients.
Pour mixture into the prepared baking dish. Cover and refrigerate for at least 6 hours (or overnight).
When ready to bake, place the baking dish on the counter to come to room temp while you preheat the oven to 350F/180C.
Bake, uncovered, for 45 minutes – 1 hour.
Notes
Leftover casserole will keep in the refrigerator for 3-4 days.
To freeze the casserole: Bake in a freezer safe pan (like a foil disposable pan) and cool completely. Wrap well in foil and freeze for up to 3 months. Defrost in the fridge the night before you plan to eat the casserole. Reheat the casserole in a 350 degree F oven for about 30 minutes, or until warmed through. You can also reheat individual slices in the microwave for about 1 minute.
Note: Recipe from my friend Sallie and adapted from Recipes and Remembrances cookbook from Etlan United Methodist Church.