4 med. red potatoes (peeled, diced and cooked)
1/4 c. butter, softened
2 tbsp. minced onion
6 frankfurters, sliced
1 can (10 3/4 oz.) condensed cream of mushroom soup
1 c. frozen peas, thawed
1 tbsp. prepared mustard
1/3 c. shredded sharp Cheddar cheese

Preheat oven to 350. In an ungreased 2 quart casserole, toss potatoes, butter and onion.

In a medium bowl, mix frankfurters, soup, peas, milk and mustard. Pour over potato mixture. Bake for 40 minutes. Top with cheese. Bake 5 more minutes or until cheese melts.