Preheat the oven to 275 degrees F. Grease an 8-inch square baking dish.

In a large skillet, heat the oil over medium-high heat. Add the meat and onion and cook until the meat is browned. Drain off any excess fat. Place the meat in the baking dish along with the vegetables, water, 1 tablespoon salt, and pepper. Cover and bake for 2-½ hours. (This can be done a day or so in advance and the mixture refrigerated.)

About 45 minutes before serving, preheat the oven to 400 degrees F. Combine the flour, baking powder, and salt for the crust in a mixing bowl. Cut in the butter or shortening until the mixture resembles coarse meal. Add the milk and stir to form a dough. Drop by the spoonful on top of the meat and vegetables, leaving a few openings for steam to escape. Bake for about 30 minutes. Serve hot.