Recipes and Cooking Open-Face Veg Burgers with Sauteed Onions 4.0 (4) For a quick vegetarian main dish recipe, it's the condiments that make these frozen vegetable patties so delicious. By BHG Test Kitchen BHG Test Kitchen The Better Homes & Gardens Test Kitchen has been in continuous operation for nearly 100 years, developing and testing practical, reliable recipes that readers can enjoy at home. The Test Kitchen team includes culinary specialists, food stylists, registered and licensed nutritionists, and other experts with Bachelor of Science degrees in food science, food and nutrition, or culinary arts. Together, the team tests more than 2,500 recipes, produces more than 2,500 food images, and creates more than 1,000 food videos each year in the state-of-the-art test kitchen. Learn about BHG's Editorial Process Published on July 5, 2010 Print Share Share Tweet Pin Email Total Time: 20 mins Servings: 4 Jump to Nutrition Facts Ingredients 2 tablespoon olive oil 1 large sweet onion, halved and thinly sliced (about 3 cups) 4 refrigerated or frozen vegetable burgers (10-oz. pkg.) 2 tablespoon mayonnaise or salad dressing 1 teaspoon prepared yellow mustard 4 1/2-inch slices ciabatta bread, toasted 1 cup fresh baby spinach leaves 2 tablespoon steak sauce Directions In large skillet heat olive oil over medium-high heat. Add onion slices and cook 8 to 10 minutes or until very tender, stirring frequently. Meanwhile, prepare burgers according to package microwave directions. In small bowl combine mayonnaise and mustard; spread mixture on one side of each bread slice. Top bread with spinach and burger. Stir steak sauce into cooked onions. Spoon onion mixture on burgers. Makes 4 servings. Print Nutrition Facts (per serving) 329 Calories 20g Fat 21g Carbs 18g Protein Show Full Nutrition Label Hide Full Nutrition Label Nutrition Facts Servings Per Recipe 4 Calories 329 % Daily Value * Total Fat 20g 26% Saturated Fat 3g 15% Cholesterol 3mg 1% Sodium 688mg 30% Total Carbohydrate 21g 8% Total Sugars 3g Protein 18g Vitamin C 5.9mg 30% Calcium 60.6mg 5% Iron 2.7mg 15% Potassium 280mg 6% Folate, total 121mcg Vitamin B-12 1.8mcg Vitamin B-6 1mg *The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.