1 Using 1/4 teaspoon shortening for each cup, grease the bottom and sides of 6 cups of a popover pan or six 6-ounce custard cups. (Or, generously spray with nonstick coating.) Place the custard cups on a 15 x10x1-inch baking pan. Set aside.
2 In a medium mixing bowl stir together the all-purpose flour, whole wheat flour, and salt until combined.
3 Add the milk, eggs, and oil; beat with an electric mixer or rotary beater about 30 seconds or until smooth.
4 Fill the prepared popover or custard cups half full.
5 Bake in a 400° oven about 40 minutes or until crusts are very firm.
6 Remove from the oven. Using the tines of a fork, immediately prick each popover to let steam escape. Serve immediately. If desired, serve with margarine or butter.