1. Preheat oven to 350 degrees F. Coat a 2-quart or 8-by-8-inch casserole dish with cooking spray and set aside. Cut sliced ham into 1/2-inch squares, or medium dice; set aside.
2. In a medium skillet over medium heat, melt butter. Add onion, garlic, and mushrooms and cook, stirring occasionally, for 4 to 5 minutes, or until mushrooms soften and darken. Remove from heat and transfer mushroom mixture to a large mixing bowl.
3. Gently squeeze sides of pouch to break apart rice and add to mixing bowl (or add cooked brown rice), along with condensed soup, thawed vegetables, diced ham, egg, and 1/3 cup of the cheese, and stir together with a wooden spoon.
4. Pour mixture into prepared casserole dish and cover with foil. Bake 30 minutes, until mixture is bubbling. Remove casserole from oven, remove foil, and sprinkle remaining 1/3 cup Cheddar cheese over top. Return casserole to oven to bake another 10 minutes, until cheese on top is melted. When done, let casserole sit 5 to 8 minutes before serving.
Source: Hannaford fresh Magazine, March - April 2008