Cut chicken breast into medium pieces (About 6-7 pieces per chicken).
Prepare the marinade. Combine the milk, eggs and salt. Place the chicken pieces into the mixture and let marinade 4 hours (or overnight).The longer it marinades, the softer the chicken will become.
Combine the ingredients for the flour mixture; the flour, paprika, pepper and salt.
Take the chicken from the marinade and coat generously in the flour mixture. (Discard of the marinade.)
Add enough oil to the skillet to completely cover the bottom of the skillet, turn on med/high heat. Once the oil is hot, fry 6-8 minutes, until chicken is crispy, turning as needed. Don't crowd the skillet. (Using two skillets works quicker.)
While chicken is frying prepare the cream mixture; combine cream of chicken soup, sour cream, water, salt, paprika and pepper.
Once chicken cooks, transfer onto a plate lined with paper towel.
Cover the bottom of a 9"x13" dish with some of the cream.
Add the chicken pieces to the casserole dish.
Completely cover with the remaining cream. (If preparing the night before and will be cooking it the following day, wait for the chicken to cool before covering with the cream.)
Add half of the cheese. Add the cooked bacon and sauteed mushrooms. Sprinkle remaining cheese.
Bake 350° for 30 minutes, covered with foil. Remove foil and continue baking another 15-20 minutes until cheese melts and cream bubbles everywhere.