Saute 1 1/2 pounds diced yellow squash in butter over medium-high heat, 1 minute. Add 1/2 cup chicken broth, 2 sprigs thyme, and salt to taste; bring to a simmer. Reduce the heat to medium low; partially cover and cook, stirring occasionally, until tender, about 8 minutes. Uncover; cook 2 more minutes. Stir in chopped parsley and salt and pepper to taste.