Maggie's Minestrone Soup

INGREDIENTS

• 1/4 cup butter
• 1/4 cup olive oil
• 2 large carrots, diced
• 1 large onion, chopped
• 2 stalks celery, thinly sliced
• 2 medium potatoes, diced
• 1 leek, trimmed,washed & thinly sliced
• 3 cups beef broth or 3 cups beef stock
• 3 cups chicken broth or 3 cups chicken stock
• 1 teaspoon salt
• 1 teaspoon pepper
• 1 (19 ounce) can diced tomatoes, & juice
• 1 zucchini, peeled & diced
• 1 (14 ounce) can red kidney beans, drained & rinsed
• 1 (14 ounce) can white kidney beans, drained & rinsed
• 1/2 cup dried spaghetti, broken into pieces
• parmesan cheese