In a large stock pot bring vegetable broth to a boil. Add mustard and cook for 1 minute. Remove greens and pat completely dry with paper towels. Process greens, walnuts, salt, pepper and garlic in a food processor for 2-3 minutes or until a paste forms, stopping to scrape down sides. With processor running, pour Olive oil and lemon juice through food chute in a steady stream, processing until smooth. Add honey and cheese and pulse 3 – 4 times or until well blended. (May need to add more salt and pepper to taste.) Serve immediately or place plastic wrap directly on pesto to help retain color. Let stand 10 minutes before serving.