Food & Cooking Recipes Martha's Greenhouse-Vegetable Soup 5.0 (1) Close Credit: Johnny Miller Prep Time: 20 mins Total Time: 50 mins Servings: 6 Packed with produce like spinach, Savoy cabbage, potatoes, carrots, and celery, this soup is both fresh-tasting and filling. Directions Heat oil in a medium saucepan over medium. Add onion, carrots, celery, and garlic; season with salt and pepper. Cook, stirring occasionally, until onion is soft, about 10 minutes. Add potato, cabbage, and stock. Bring to a boil, then reduce heat to low and simmer, partially covered, until flavors are melded and cabbage and potato are very tender, 20 to 25 minutes. Stir in spinach and parsley and cook 5 minutes (or 1 minute if using baby spinach—you don't want it raw, but you do want to maintain some of its color). Serve, sprinkled with cheese, drizzled with oil, and with lemon wedges on the side.