Prepare cornmeal pastry. In a mixing bowl combine flour, cornmeal, and salt; cut in shortening or lard till mixture resembles coarse crumbs. Sprinkle 1 tablespoon of the water over part of the mixture; gently toss with a fork. Push to side of bowl. Repeat till all is moistened. Form dough into a ball. Divide in half. On a lightly floured surface roll half the dough to a circle about 10 inches in diameter. Ease pastry into 9-inch pie plate. Trim to 1/2 inch beyond edge of baking dish; set aside.

In a large skillet cook sausage and onion over medium-high heat till sausage is browned and onion is tender; drain. Stir in mushrooms, olives, pimiento and flour. Add water and cook over medium heat 5-6 minutes, stirring occasionally. Remove skillet from heat; stir in Mozzarella cheese and Parmesan cheese. Set aside.

For top crust, roll out the remaining dough. Spoon sausage mixture into the pastry-line pie plate. Top with pastry for top crust. Trim top crust 1/2 inch beyond edge of baking dish. Fold extra pastry under bottom crust; flute edge.

Combine egg and water; brush egg mixture atop pastry, cut slits for escape of steam. Bake in a 400º oven for 30 minutes of until crust is golden. Let stand 5 minutes before serving.