Add the butter, wine, and broth to a 10-inch skillet and warm over medium-high heat until butter is melted. Add the cherry tomatoes and cook, stirring regularly until they begin to shrivel. Sprinkle with the pinch of sugar, ¼ teaspoon each salt and freshly ground black pepper, and cook another 5 minutes or so, until tomatoes have collapsed but are still intact. You should have cooked tomatoes in just a small amount of sauce. Turn the heat off and carefully remove the skins from the tomatoes, using a table fork and a small sharp knife, if desired. Cover and set aside.