A gentle simmer keeps the vegetables in the soup slightly firm, so they maintain their texture during freezing and reheating.
2 tablespoons olive oil
2 cups thinly sliced leek, white and light green parts only (about 2 leeks)
1 cup thinly sliced carrot
1 cup thinly sliced celery
2 large garlic cloves, minced
2 tablespoons tomato paste
8 cups unsalted chicken stock (such as Swanson)
1 (14.5-ounce) can unsalted diced tomatoes, undrained
1 (14.5-ounce) can unsalted cannellini beans, rinsed, drained, and divided
2 cups chopped yellow squash
2 cups chopped zucchini
1 cup chopped red bell pepper
1 cup fresh green beans, cut into 1-inch pieces
1/2 cup uncooked ditalini pasta
3/4 teaspoon kosher salt
1/2 teaspoon black pepper
5 ounces Lacinato kale, stemmed and chopped
1/4 cup homemade or refrigerated pesto (such as Buitoni)
2 ounces Parmesan cheese, grated (about 1/2 cup)
How to Make It
Heat a large Dutch oven over medium heat. Add oil; swirl to coat. Add leek, carrot, celery, and garlic; cover and cook 5 minutes, stirring occasionally (do not brown). Add tomato paste; cook 2 minutes, stirring constantly. Add stock and tomatoes; bring to a boil. Reduce heat to low, and simmer 15 minutes.
Place 1 cup cannellini beans in a small bowl; mash with a fork. Add mashed beans, remaining cannellini beans, squashes, bell pepper, green beans, pasta, salt, and black pepper to pan. Increase heat to medium; cook 10 minutes. Stir in kale; cook 2 minutes. Place 2 cups soup in each of 8 bowls, or follow freezing instructions. Top each serving with 1 1/2 teaspoons pesto and 1 tablespoon Parmesan cheese.
FREEZE: Cool soup completely. Freeze flat in a large zip-top plastic freezer bag for up to 2 months.
THAW: Microwave soup in bag at MEDIUM (50% power) 5 minutes or until pliable.
REHEAT: Pour soup into a large Dutch oven. Cook over medium heat, partially covered, 20 minutes or until thoroughly heated. Serve with pesto and Parmesan cheese.