1. Combine water, cornmeal and salt in microwave-safe casserole; stir well. Cover tightly with plastic wrap; vent one corner.
2. Microwave at full power (100 percent) for 10 minutes. Carefully remove plastic wrap. Stir. Cover with paper toweling. Microwave 10 minutes, stirring twice. Pour into greased 10-inch pie pan; cool. Refrigerate until firm, 1 hour.
3. Saute sausage, onion and garlic in skillet until sausage is no longer pink, about 8 minutes. Add tomatoes; cook, breaking up tomatoes, for 14 minutes, until slightly thickened.
4. Heat broiler. Cut polenta into 4 wedges. Place on broiler pan.
5. Broil 1 minute per side or until lightly browned. Place on serving platter. Pour sauce over and serve. Makes 4 servings.