Preparation Melt butter in large deep skillet over medium-high heat. Add pork; brown on all sides, about 5 minutes total. Add parsnips, squash, onions, broth, and thyme; bring to boil. Reduce heat to medium-low. Cover and simmer until pork is just cooked through, about 10 minutes. Transfer pork to plate and tent with foil to keep warm. Continue simmering, uncovered, until vegetables are tender and liquid is slightly reduced, about 5 minutes longer. Stir mustard into sauce. Season to taste with salt and pepper. Cut pork diagonally into 1/2-inch-thick slices and serve with sauce and vegetables.
Preparation Melt butter in large deep skillet over medium-high heat. Add pork; brown on all sides, about 5 minutes total. Add parsnips, squash, onions, broth, and thyme; bring to boil. Reduce heat to medium-low. Cover and simmer until pork is just cooked through, about 10 minutes. Transfer pork to plate and tent with foil to keep warm. Continue simmering, uncovered, until vegetables are tender and liquid is slightly reduced, about 5 minutes longer. Stir mustard into sauce. Season to taste with salt and pepper. Cut pork diagonally into 1/2-inch-thick slices and serve with sauce and vegetables.