Round out a traditional holiday menu (as host or as guest) with this simple side.
In a large skillet, combine onions, butter, sugar, and 1 1/2 cups water; bring to a boil. Reduce to a simmer, and cook over medium-low, stirring occasionally, until onions begin to soften and liquid has evaporated, 15 to 20 minutes.
Continue to cook until golden, about 8 minutes, tossing occasionally. Add 1/4 cup water, and cook until onions are glazed, about 10 minutes more. Remove from heat, and stir in vinegar and thyme.