Slow Cooker Cream of Zucchini Soup

Ingredients

• 1 small onion, minced
• 3-1/2 to 4 cups grated zucchini with peel
• 2 (14 ounce) cans chicken broth
• 1 teaspoon seasoned salt
• 1 teaspoon dried dill weed
• 1/2 teaspoon white pepper
• 2 tablespoons butter, melted
• 1 (8 ounce) carton sour cream