This chicken and rice casserole would be yummy enough with just the salsa, Cheddar and sour cream. The bounty of sauteed mushrooms is an oh-so-good bonus.
Avocados, onion, chopped tomato, garlic and a splash of lovely lime juice. That 's all. Well, maybe a dash of salt and pepper and an hour or so in the refrigerator. Fabulously easy.