Beef Wellington Pie

1 1/4 to 1/2 lb hamburger
1 medium onion, diced
1 c shredded cheese
1 can cream of mushroom soup (undiluted)
1 egg well beaten
2 pkg Pillsbury crescent rolls

Brown hamburger and onion together. When no longer "raw" add cheese, stirring often. Next, add soup, until all mixed. Add 1/2 of beaten egg and stir quickly. Let simmer while you prepare 1 pkg of rolls. Shape into 9" pie pan like a pie crust. Fill w/hamburger mixture. Use the other pkg of rolls for top. Brush last of egg on top. Bake as directed on roll pkg.