Heat oven to 350°F. In ungreased 13x9-inch (3-quart) glass baking dish, mix ham, broccoli, potatoes and Cheddar cheese.
In large bowl, beat eggs, milk, sour cream, salt and pepper with wire whisk. Pour egg mixture over ham mixture. (If desired, cover and refrigerate casserole at this point up to 8 hours or overnight.)
Bake uncovered 45 to 50 minutes or until center is almost set.
Meanwhile, in small bowl, stir remaining ingredients with fork until crumbly. Sprinkle crumb mixture on ungreased cookie sheet. Bake on lower oven rack for last 20 minutes of casserole bake time, stirring once. Sprinkle over casserole before serving.