I write about food, mostly for Yoga Journal. My last column in the November issue was about the health benefits of eating soup.Here's my recipe for beet soup. It's Solstice, the shortest days of the year. The earth becomes more quiet. It's time to eat what digs deep, which are the root vegetables. I particularly love beets because they are so red, earthy and powerful.Beet Soup1 medium onion, peeled and chopped2 tablespoons olive oil or butter3-4 large beets (about 1-1/2 pounds,) rinsed, peeled and cubed4 cups water or vegetable stocklemon juice to tastedill to tastesalt to tasteplain yogurt or sour cream to tastebeet greens, chopped (optional)1. Saute the onion in the butter or oil in a heavy 4-quart pot over medium heat until soft, about 5 minutes.2. Add the beets. Saute for 5 more minutes.3. Add the water or stock. Bring to a boil and skim the foam from the top. Continue cooking, covered, over medium low-heat until vegetables are soft, about a half hour.4. Add lemon juice and salt.5. Optional Puree with a hand blender if you like a smoother consistency and aren't including cabbage or beet greens.6. Serve hot or cold, topped with fresh or dried dill and a dollop of plain yogurt or sour cream.