Pound pork into 1/4 inch thickness between plastic wrap or wax paper.
Melt 3 tablespoons butter in large saute' pan and add pears, onions and thyme. Salt and pepper to taste. Let cook until pears turn golden and onion is soft.
In another pan, melt 1 tablespoons butter and add one layer of pork slices. Salt and pepper pork. Cook pork about 2 minutes per side, or until just cooked through and a nice crust starts to form (you will have to cook pork in batches).
Arrange pork on a serving platter and slather the pear-onion mixture over the top.