Chinese Pepper Steak

INGREDIENTS

• 1 pound beef top sirloin steak
• 1/4 cup soy sauce
• 2 tablespoons white sugar
• 2 tablespoons cornstarch
• 1/2 teaspoon ground ginger
• 3 tablespoons vegetable oil, divided
• 1 red onion, cut into 1-inch squares
• 1 green bell pepper, cut into 1-inch squares
• 2 tomatoes, cut into wedges