Melt butter in a medium saucepan over medium-high heat.
2 tablespoon butter
Add onion, carrot, and celery sauté until onion is translucent.
1 onion, diced, 1 large carrot, diced, 2 celery sticks, diced
Next, add the garlic and ginger. Cook for 1 minute more.
1 tablespoon fresh garlic, minced, 1 teaspoon fresh ginger, grated
Add chicken broth and cubed sweet potatoes.
3 cups chicken broth or vegetable stock, 2 medium sweet potatoes, peeled and cubed into 1-inch pieces
Bring to a simmer and cover, reduce heat to medium-low and simmer for 20 minutes or until you can pierce potatoes with a fork.
Add salt and black pepper.
salt and pepper to taste
Using an immersion blender, puree the soup until smooth. Alternatively, pour the soup mixture carefully into a blender and puree.
Stir in cream (optional) and serve.
¼ cup heavy cream (optional), fresh tarragon (optional)