Cream of Asparagus Soup

Ingredients
2 pounds asparagus
1 large onion, chopped
3 tbsp unsalted butter
5 cups chicken broth
1/2 cup heavy cream
fresh lemon juice to taste
salt and pepper

Directions
1. Break off tips of asparagus.Cut asparagus into 1/2-inch pieces.
2. Cook in a skillet over medium heat with onion in butter for 5 minutes.
3. Add asparagus pieces with salt and pepper to taste, then cook 5 minutes.
4. Add stock and simmer until asparagus is tender. Cool slightly.
5. In a blender, puree sauce.
6. Return to the skillet over low heat. Stir in cream; stir in lemon juice. Season with salt and pepper.