Nigel Slater’s recipes for Roasted Onions with Polenta and Cheese and Onion Tart | Food

I I’ve been cooking a pan of onions for a good half hour, stirring them from time to time, while I prepare the pastry. They went from crunchy to soft, from ivory to nutty, and most importantly, from tangy to soft and sweet.

There is no point in squeezing an onion – other than dipping them in batter and dipping them in bubbling oil. They need time and that’s what they’re getting today. Later, when they are shiny and translucent, they will join eggs and cream, and mustard and cheese in a pastry – the second of two cheese and onion dinners this week. This will be accompanied by a spinach salad and perhaps speckled Castelfranco and a few citrus wedges.

Winter is the best time to cook onions. Kept for several months, their flesh contains less water and therefore produces less steam when cooking. Without excess humidity, they brown more effectively. A bit of sticky Marmite-like dough will appear on the pan and that’s a good thing. Stir it around so it can gently stick to the shiny alliums. For this pie, they are ready when you can crush them effortlessly between your thumb and forefinger.

There were onions in the oven again yesterday, this time grilled on one side, left to cook in the oven for almost an hour, then brought to the table on a bed of soft, cheesy polenta. When it comes to cooking onions, it’s best to take the scenic route.

Roast onions, gruyere polenta

The onions should be tender all the way through. Pierce them with a metal skewer to check. If the cut edges are browned here and there, all the better. For 4 people

onions 4, small to medium
peanut or vegetable oil 4 tablespoons

For the polenta:
water 500ml
milk 250ml
coarse polenta 125g
gruyere 75g, grated (or a good sharp cheddar)
butter 50 grams

For the crumbs:
peanut or olive oil 2 tablespoons
fresh white breadcrumbs 60g
parsley leaves a good handful, chopped
dill leaves 2 tablespoons, chopped

Preheat the oven to 200°C/gas mark 6. Peel the onions, cut them in half and place them cut side down in a large roasting pan. Drizzle with oil, salt. Bake for 40 minutes until the underside is nicely toasted, then turn the onions and cover with foil. Return to the oven for another 20 minutes. They should be tender and nicely browned. If there are caramelized juices in the box, that’s good news: we’ll use them later.

When the onions are almost cooked, prepare the polenta. Bring the water and milk to a boil, add 1 teaspoon of salt and reduce the heat so that the liquid simmers. Pour the polenta either into a pitcher or spray it in a steady stream with your hand (if you add it all at once, it will form lumps). Stir immediately, taking care to protect your hands from the Vesuvius-like bubbling that ensues. Reduce the heat so that the simmer is really slow and gentle, then stir regularly for 25 to 30 minutes.

Prepare the breadcrumbs: heat the oil in a shallow pan, then pour in the breadcrumbs. They will sparkle in the oil. Mix them a little so that they color evenly. They should be slightly crunchy and a deep golden color. Stir in chopped parsley and dill.

Add the cheese and butter to the polenta and season. I like to include a grind of black pepper at this point. Pour the polenta into a serving dish, place the roasted onions on top, then pour the roasting juices from the pan. Sprinkle with toasted breadcrumbs.

Cheese and onion tart

There’s something rare about this Welsh tart, so feel free to use even more mustard if you like. It goes well with a winter salad, like spinach and orange. For 6 persons

For the pastry:
flour 150g
butter 80g
Egg yolk 1
Frozen water 1-3 tablespoons

For the filling:
onions 3, large, about 750g
butter 50 grams
olive oil 2 tablespoons
egg 1, large
egg yolks 2, large
whole grain mustard 1 tablespoon
double cream 250ml
Cheddar 125g, grated

You will need a 20cm tart tin with a removable base. Prepare the dough by turning the flour and butter into fine crumbs. (You can also rub the butter into the flour with your fingertips until it resembles breadcrumbs.) Mix the egg yolk and a tablespoon or two of ice water to form a thick paste and rollable.

Pour the dough onto a lightly floured board, form a thick disk then wrap it in baking paper then let it rest in the refrigerator for 30 minutes.

Prepare the filling: peel the onions and cut them into thin segments. Heat the butter and oil in a deep frying pan over medium heat, add the onions and cook, stirring regularly, for a good 30 minutes. It seems like a long time, but slow cooking will leave the onions especially soft and sweet. Stir them every few minutes, making sure to incorporate any sticky caramelized sugars that form at the bottom of the pan.

Remove the dough from the refrigerator and place it on a floured board. Spread it to fit the tart base. Lower the puff pastry into the tart pan, gently pushing it into the corners and sides. Cut off any excess dough, then let the dough rest a second time, in the refrigerator or freezer, for 20 minutes. I know this sounds like a drag, but it will keep the sides from shrinking while cooking.

Set the oven to 190°C/gas mark 5 and place a baking tray in the oven. You will bake the pie on top.

Fill the tart shell with parchment paper and dried beans, then place it on the baking tray already in the oven. Bake for about 20 minutes, then carefully remove the paper and beans. If the dough is not dry to the touch, return it to the oven for a few minutes, then remove it and set aside.

Reduce the oven to 180°C/gas mark 4. Mix the whole egg and the yolks with a fork, then add the mustard, cream and cheese, a little salt and pepper, then add the onions. Grind a little black pepper there, then fill the tart base with the mixture. Bake for about 30 to 35 minutes until the surface is golden brown. Let rest for at least 20 minutes before slicing.

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