Creamy Asparagus Soup - Ellie Krieger

Ingredients

• 2 medium leeks
• 2 tablespoons olive oil
• 1 medium white potato (about 5 ounces)
• 1 teaspoon herbs de Provence or 1 teaspoon dried thyme
• ¾ teaspoon salt
• ¼ teaspoon freshly ground black pepper
• 3 cups low-sodium chicken broth or vegetable broth
• 2 pounds asparagus, trimmed and cut into 1 inch pieces
• 1 teaspoon fresh lemon juice
• 4 teaspoons low-fat plain yogurt, optional