Baked Spicy Onion Slices (Alice Waters)
Onions cooked this way can be served warm or cold, as a side dish or by themselves.
Peel them, slice them a half inch thick, season well with salt, and place them on a well-oiled baking sheet. Brush the exposed sides of the onions with olive oil and bake them in a preheated 375 degree oven for about 30 minutes, or until the onions are soft, and browned on their undersides.
When the onions are cooked, place them carefully in a shallow dish, keeping the slices intact. Pour over them a vinaigrette made with 1 part sherry vinegar, 4 parts extra-virgin olive oil, salt, and a pinch of cayenne or hot pepper flakes.
Let the onions marinate in the vinaigrette for about 20 minutes. Serve them cool, or warm them gently in the oven.