To prepare a summer squash and sausage stew recipe, you will first need to prepare your ingredients. You will need the following ingredients: 14 cup chopped thyme, 1 tablespoon kosher salt, 2 tablespoons olive oil, and 1 teaspoon ground black pepper. Cook the ingredients over medium heat, stirring occasionally, until the vegetables are tender, about 20 minutes. Add the sausage and cook until it is no longer pink in the center, 10 to 15 minutes more. Stir in 2 cups chopped parsley. Serve the stew with mashed potatoes and sour cream.