In large skillet cook meat and onions until meat is lightly browned. Add salt and pepper. Add drain beans and soup; pour into greasted 1.5 quart casserole. Mash potatoes while hot; add milk and egg. Season with salt and pepper. Spoon in mounds over casserole. Sprinkle potatoes with cheese. Bake in 350 oven for 25 to 30 minutes. Or prepare 4 servings packaged instant potatoes according to package directions except reserve milk. Add egg and season with salt and pepper to taste. Add enough reserved milk so potatoes are stiff enough to hold shape.