Roasted Beet Soup With Creme Fraiche

Ingredients

• 1/2 pound red beets (about 3 medium)
• 1 1/2 teaspoons butter
• 1 1/2 teaspoons olive oil
• 1 leek (white and pale green parts only), chopped
• 1 small onion, thinly sliced
• 1 celery stalk, chopped
• 1/8 teaspoon ground ginger
• 1/8 teaspoon ground allspice
• 1/8 teaspoon ground white pepper
• 2 cups water
• 1 small bay leaf
• 1 fresh thyme sprig
• 1 fresh parsley sprig
• 1/4 cup whipping cream
• 2 tablespoons crème fraîche or sour cream