Beef with Red and Yellow Bell Peppers

Name: Beef with Red and Yellow Bell Peppers
Ingredients: 2 large garlic cloves, minced; 2 tablespoons low-sodium soy sauce; 2 tablespoons dry sherry; 1 teaspoon sugar; 1/2 teaspoon freshly ground pepper; 1 tablespoon plus 2 teaspoons vegetable oil; 1 pound beef eye of round, halved lengthwise and sliced crosswise 1/16 inch thick; 1 cup chicken stock; 2 tablespoons oyster sauce; 1 teaspoon cornstarch; 1 red onion, sliced 1/2 inch thick; 2 yellow bell peppers, cut into 2-inch squares; 1 red bell pepper, cut into 2-inch squares; 1 teaspoon Chinese chili-garlic paste; 1/2 teaspoon Asian sesame oil; 1/4 cup coarsely chopped basil