Meanwhile, to make mustard pears, melt butter in a pan on medium. Add sugar, vinegar, mustard, ground cloves and ¼ cup of water. Simmer, stirring, for 2-3 mins, or until well-combined. Add pears and simmer for 5 mins, or until pears have softened and sauce has thickened slightly. Serve mustard pears with pork and roast potatoes.