Creamy Potato Leek Soup

Name: Creamy Potato Leek Soup
Prep time: 5 min
Cook time: 25 min
Total time: 30 min
Yield: 4
Ingredients: Ingredients; 3 large leeks (white and light green parts only), thinly sliced; 4 large potatoes, peeled and diced; 2 tablespoons butter; 1 tablespoon olive oil; 4 cups vegetable or chicken broth; 1 cup heavy cream or half-and-half; 2 cloves garlic, minced; 1 teaspoon fresh thyme (or 1/2 teaspoon dried thyme); Salt and pepper, to taste; 1/4 teaspoon ground white pepper (optional, for extra flavor); Fresh chives, chopped (for garnish)