Deep Dish Cowboy Pie

4 cups all-purpose flour
1 3/4 tablespoons baking powder
3/4 teaspoon salt
3/4 cup vegetable shortening
1 1/4 cups milk
1/2 cup Cheddar cheese
1/4 cup diced green chives or green onions
1 1/2 pounds lean hamburger
1/2 cup chopped onion
Salt and pepper to taste
1/4 teaspoon garlic powder
1 (8 ounce) can tomato sauce
1 ripe tomato, peeled and sliced
1 cup sliced fresh mushrooms
1 1/2 cups shredded mozzarella cheese

Heat oven to 375 degrees F.

In a large bowl combine the flour, baking powder, salt and vegetable shortening. Cut shortening into dry ingredients with a fork or pastry blender. Add cheese, chives, then milk. Mix with a fork to form dough. Pat dough on bottom and up sides of a greased 10-inch plate. Roll out remaining dough and make biscuits. (Will make 10 to 12 biscuits.) Set aside.