Melt butter in large skillet. Add sliced mushrooms, cook 5 minutes. Remove mushrooms with slotted spoon, set aside.
Combine flour, salt, pepper, and nutmeg in a container. Coat chicken pieces with flour mixture. In same skillet in remaining butter, brown chicken pieces on all sides. Add more butter or cooking oil if needed.
Stir in cream, marsala or sherry, and mushrooms. Heat to boiling. Reduce heat to low, cover, and simmer 10-15 minutes if chicken is cooked, 30 minutes if chicken is raw, or until cooked through and fork tender.
To make cauliflower rice, cut 1 head of cauliflower into pieces. Mix in food processor a few handfuls at a time until cauliflower reaches a rice-like consistency. Coat large skillet with olive oil and heat on stove. Add riced cauliflower and stir in with the oil. Cover the skillet and steam on low heat for five minutes. Fluff and serve.