Chicken Tortellini Casserole

1/2 Stick of Butter
8 oz package Cheese Tortellini
8 oz Monteray Jack Cheese, cut into slices and some grated
4 Chicken breasts cubed
3/4 cup chopped white onions
1 tbsp chicken bullion granuals
1 cup chicken broth
1 tsp Sugar
1 4 oz can sliced mushrooms, drained
1/2 cup sour cream

Cook Tortellini for 5 min less then package directions. Drain, put tortellini in a lightly greased 9x13 pan. Place thin slices of Jack Cheese over the tortellini. Coat Chicken lightly in flour and brown in a skillet with 1/2 of the butter. Put chicken over the top of the cheese layer. In the skillet add the remaining butter and onions. Cook until translucent. Add bullion, broth, sugar, and mushrooms. Bring to a boil. Cook for 5 min. Add sour cream and remaining grated Jack Cheese. Stir. Pour sauce evenly over the chicken layer. Bake 300 for 45 min. Let stand 10-15 min before cutting.