Onions are one of those foods it is easy to take for granted. Yet they are an essential ingredient in a variety of dishes. Anybody who does much cooking probably uses onions several times a week. I can think of countless recipes which start with the words: “sauté onions until they are translucent.”
Because they are available year round, it is easy to forget that onions have a season. Mid summer, from mid-July to the end of August, is the time of year when onions are freshest and most abundant. This is the time when the big onion growing areas of Texas, New York and California are in peak production, and you will see big, beautiful red, white and yellow onions at the supermarket.
This is also the time of year when the best-known varieties of sweet onions come to market. On the east coast, where I grew up, people would wait eagerly for the Georgia-bred Vidalias, an onion of legendary sweetness. Here on the west coast, onion aficionados welcome this as the time when for a few short weeks, you can buy Walla Walla sweet onions.
Hailing from Walla Walla County in southeastern Washington, the progenitor of this famous onion was a sweet onion grown on the Mediterranean island of Corsica. Brought to the U.S. in the late 1800’s by a French soldier, it was quickly adopted by the immigrants who settled the Walla Walla valley.
Over succeeding generations, growers hand selected the sweetest, biggest, and roundest onions from each year’s crop. The result is an onion so sweet, crisp and mild that some people eat them like apples. More often, they are sliced and used raw in salads or on sandwiches.
Walla Walla onions caramelize beautifully. They are delicious brushed with olive oil and baked. And they make the best deep fried onion rings on the planet. The reason Walla Walla onions are so sweet is because they have a low sulfur content. Sulfur helps onions have a long shelf life, though, which means that Walla Walla onions are much more perishable than regular yellow onions. If you buy them, plan to use them quickly!
The following recipe is from Alice Waters’ book Chez Panisse Vegetables. If sweet yellow onions are out of season, this recipe also works well for sweet red onions, which are available almost year-round.
Baked Spicy Onion Slices
Onions cooked this way can be served warm or cold, as a side dish or by themselves. Sweet juicy yellow onions are best for this recipe. 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.