In a large pot, sauté chopped onion and garlic in some olive oil until soft. Add diced potatoes and blanched asparagus spears. Pour in enough vegetable broth to cover the vegetables. Bring to a boil, then reduce the heat and simmer for 20-25 minutes, until the potatoes are tender. Puree the soup with an immersion blender until smooth. Season with salt, pepper, and a pinch of nutmeg. Serve hot with croutons and chopped fresh parsley.
