Pumpkin Lemongrass Soup FSSeattle. 1. Quarter 5 sugar pumpkins. Remove seeds. Roast 30 min until tender. 2. Sweat 2 onions, 4 carrots, 2 celery stalks, 4 lemon grass stalks (roughly chopped) w/ 4 garlic cloves in pot until soft. 3. Remove pumpkins. Scoop out flesh & add to pot w/ 2 gallons vegetable stock. Bring to boil, then simmer for 30 min. Purée soup throughly & season. 4. (5) Garnish plates w/ golden raisins & diced granny smith apples. Pour soup over & top w/ a mini apple fritter.