Easy Shepherds Pie

1 lb ground beef
1/2 cup chopped onion
1/2 tsp salt
1/4 tsp pepper
1 can cut green beans, drained
1 can tomato soup
6 potatoes, peeled, boiled, and mashed
1/2 cup milk
1 tsp salt
2 cups grated cheddar cheese

Preheat oven to 350 degrees. Brown ground beef in a saute pan. Add onion, salt, and pepper. Saute until onion is tender. Put meat mixture into the bottom of a greased 9X13 pan. I use a smaller pan so the layers are a little thicker. Pour the green beans on top of the meat mixture and then spread the tomato soup over the beans. Combine the mashed potatoes with milk and salt. Mix well. Spread the potatoes on top of the tomato soup. Top with grated cheese. Bake for 30 minutes.