Heat ove to 350F and grease a 9 X 13 baking dish.
Mix vegetables, meats and 1 cup of shredded cheese in large mixing bowl.
Stir together cream of mushroom soup, sour cream and eggs till smooth and combined in a small mixing bowl.
Pour sauce over vegetable/meat mixture and stir to coat.
Spoon sauce-coated vegetables, ham and cheese into prepared baking dish.
In a small bowl, stir together dry ingredients for topping mixture.
Stir butter in with a fork. Mixture should be crumbly and slightly damp in small clumps of dough, but not wet. Add up to two tablespoons of water a little at a time if mixture is too dry and flour like.
Evenly sprinkle topping over the prepared casserole mixture.