Food

Fish on caramelized onions becomes French onion tart

Onions will brown in 10 minutes, but caramelizing, which takes more than an hour, is a slower, more purposeful process in which the cut-up rounds cook in olive oil or butter, until sharp, pungent rings turn into sweet, tender, golden mouthfuls. You can use large Spanish or white onions or sweet varieties, such as Vidalia or Walla Walla, but for a slightly less cloying, jammy mass, opt for regular yellow onions. Once they’re caramelized, they can be put to many good uses, including as a bed for roasting fish fillets.

For a second meal, use some of the sweet, jammy onions to cover an easy pressed-in pastry crust for a Provencal-style tart. Sprinkle the top with Nicoise olives and Parmesan, which together bring just the right amount of contrasting saltiness. Yes, five pounds of onions is a lot to peel and slice — and may even bring you to tears — but the resulting meals will have you smiling through them.

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(For roast fish, onion tart)

1½ pounds thickly cut hake,

pollock, perch, cod, or

other white fish

½ cup (1 stick) unsalted

butter

3 tablespoons grated

Parmesan

1 cup Nicoise or Kalamata olives

5 pounds (about 10 large) yellow onions

2 cloves garlic

Few sprigs fresh parsley

4 sprigs fresh thyme

Salt and pepper

1¼ cups flour

5 tablespoons olive oil

1 bay leaf

½ teaspoon smoked paprika

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