Heat oven to 325 degrees. Lightly butter 2-quart casserole. In medium saucepan, bring water, 2 T butter, garlic powder ad pepper to a boil. Remove from heat; stir in potato flakes, milk, cheese, mustard and eggs until well blended. Place potato mixture in buttered casserole. Using back of spoon, make indentation in potato mixture around edge of casserole 2 inches wide by 1 inch deep. Bake uncovered at 325 degrees for 20 to 25 minutes or until thoroughly heated. Meanwhile, cook vegetables according to package directions; drain. Add 2 T butter, stir to coat. Spoon cooked vegetables into indented ring in hot potato mixture.