1. Cut steak across grain into 1/4-inch slices; cut slices into 1/2-inch-wide strips. Cut strips into 3-inch-long pieces. Combine steak pieces, soy sauce, wine, sugar, and black pepper.
2. Heat a 14-inch wok over high heat. Add 1 tablespoon oil to wok, swirling to coat. Add onion and garlic to wok; stir-fry 30 seconds or until onion begins to brown. Add red and green bell peppers to wok; stir-fry 2 minutes or until crisp-tender. Spoon bell pepper mixture into a large bowl.
3. Add 1 1/2 teaspoons oil to wok, swirling to coat. Add half of steak mixture to wok; stir-fry 1 minute or until browned. Add cooked steak mixture to bell pepper mixture. Repeat procedure with remaining 1 1/2 teaspoons oil and remaining steak mixture. Return steak mixture to wok; sprinkle with salt. Stir-fry 1 minute or just until heated. Serve over rice.
Wine note: When it comes to wine, this simple beef recipe needs care because green bell peppers can make many red wines taste green and weedy, while soy sauce can make reds taste hollow. So choose a wine with a lot of fruitiness and berry flavors. A great choice is traditional Beaujolais—especially one of the cru Beaujolais such as Moulin-à-Vent. The Georges duBoeuf Beaujolais Moulin-à-Vent (Flower Label) 2006 from Burgundy, France, is $14. —Karen MacNeil