Heat oven to 350°F. Cook pasta according to package directions; drain well. In large bowl, whisk together remaining Pasta Shell ingredients. Add pasta; toss to coat. Arrange pasta in 9-inch pie dish, pressing down and up side to form shell; set aside.
Meanwhile, heat large nonstick skillet over medium heat until hot. Add Ground Beef; cook 8 to 10 minutes, breaking up into 3/4-inch crumbles and stirring occasionally. Stir in chili powder, 1 teaspoon garlic powder, 1/2 teaspoon salt and cumin. Stir in tomatoes and zucchini. Gently simmer 3 to 5 minutes or until liquid is almost evaporated, stirring occasionally.
Stir sour cream into remaining beef; spoon into pasta shell. Place 1 cup cheese in center, leaving 2-inch border around edge. Bake in 350° oven 15 minutes or until heated through.
To serve, cut into wedges.
Nutrition information per serving: 582 Calories; 153 kcal Calories from fat; 17 g Total Fat; 8.5 g Saturated Fat; 0 g Trans Fat; 1.1 g Polyunsaturated Fat; 3.9 g Monounsaturated Fat; 158 mg Cholesterol; 1088 mg Sodium; 57 g Total Carbohydrate; 4.1 g Dietary Fiber; 47 g Protein; 5.7 mg Iron; 816 mg Potassium; 10.6 mg Niacin; 0.6 mg Vitamin B6; 2.9 mcg Vitamin B12; 7.6 mg Zinc; 61.3 mcg Selenium; 144.2 mg Choline;