3/4 pound large peeled and deveined shrimp, thawed if frozen
8 tostada shells
Lime wedges, optional
Stir together drained tomatoes, avocado and onion in small bowl to make salsa; set aside. Place beans and 1/4 teaspoon chile pepper in small microwave-safe bowl; cover. Microwave on HIGH 2 minutes or until beans are hot, stirring at end.
Heat oil in large skillet over medium-high heat. Sprinkle shrimp with remaining 1/2 teaspoon chile pepper; add to skillet and cook 3 to 5 minutes or just until shrimp turn pink, stirring frequently.
Spread about 1/3 cup refried beans on each tostada shell. Top each evenly with salsa and shrimp. Serve with lime wedges, if desired.