1 (10 oz.) pkg. frozen peas
1 lb. ground beef
1/2 c. chopped onion
2 c. hot water
1 can cream of mushroom soup
2 tsp. mustard
1 pkg. Hamburger Helper Potatoes Stroganoff

Heat oven to 375 degrees. Rinse peas in cold water to separate and drain. Brown beef and onion. Stir in peas, potatoes, sauce mix, water, soup and mustard. Put in 2 quart casserole or oblong baking dish. Cover and bake about 45 minutes to 1 hour.