Preheat oven to 400 degrees. Mix 2/3 C Bisquick and 1 egg with 1/8 C H2O and Spread into greased 9" round glass casserole dish.
Mix 3 cubed/diced cooked chicken breasts with 1/2 a 16 oz jar of Salsa and spread on top of Bisquick layer in dish. Bake for 15 minutes.
Remove from oven and top with 1&1/4 C Shredded Cheese (Taco Blend Mild Cheddar, whatever your preference) and return to the oven and bake 5 minutes longer or until the cheese has melted.