Avocado Chicken

I made this for the first time the other night and it was AMAZING. It definitely requires a trip to the grocery store- but its so worth it and its pretty easy to put together.

3- 4 chicken breasts
Butter
½ c. chopped white onion
1 clove minced garlic
1 pkg. fresh sliced mushrooms
2 Tbs. flour
1 tsp. celery salt
white pepper
½ c. chicken broth
½ cup white grape juice
2 avocados
1 ½ c. grated Monterey jack cheese

Cut chicken in half or pound til its thin. Sprinkle both sides with salt, black pepper, and flour. Saute with butter in large skillet until browned, but not cooked all the way through. Put chicken in 9X13 pan and set aside. In the same skillet put ¼ cup butter (or less, if desired) and sauté the onion, garlic, and mushrooms until soft. Add 2 Tbs. flour and celery salt, white pepper, chicken broth, and juice. Thicken. Stir in mashed avocados and ½ cup cheese. Pour sauce over chicken in pan and sprinkle remaining (1 cup) cheese on top. Bake at 350 for 25 minutes or until sauce is bubbly and cheese is light brown. I broiled mine for a few minutes at the end for crispy, brown cheese. Serve over noodles (I used spaghetti).