Serves 8 INGREDIENTS 2 tablespoons olive oil 1 tablespoon unsalted butter 2 medium red onions, sliced thin in rounds 1 sheet puff pastry, pre made 1 tablespoon sugar in the raw 8 to 10 slices Iberico ham 1 tablespoon fresh thyme leaves 1 egg, beaten with 1 teaspoon water and pinch of salt Salt and…