What can I cook in a hot oven as it cools?

I don’t want to waste the residual heat from my cooling oven. What can I cook or bake in there?
Kay, Sheffield
“Kay could use her cooling oven to preserve many things,” says Mark Birchall, chef-patron of Moor Hall in Lancashire. Herbs that are past their best (“or those in need of cutting back, like rosemary, for instance”) can be dried on an oven rack, then stuffed into a roast chicken, say, while bread that’s on its way out can also be dried (cut the crusts off first) in a cooling oven and blitzed into breadcrumbs.

Alternatively, turn tomatoes into future treasures, says Sam Grainger, chef-owner of Belzan in Liverpool. “Halve them, add salt and a little oil [so they don’t stick], and put in a cast-iron skillet or pan. Leave them in the hot oven until it’s cool, and they’ll get better and better the longer they’re in there.” He adds his oven-dried tomatoes to salads and ramen, or turns them into soup or sauce, though for the latter two, he recommends peeling them first: “The skin doesn’t blend, so everything will be bitty otherwise.”

Toasting nuts or spices is another use for a cooling oven, says former Bake Off star Rahul Mandal, whose new book, Showstopping Cakes, is out in October. “Toasting oats, nuts and seeds for 10-15 minutes is a great way to increase their shelf-life,” says Mandal, who stores them in an airtight container, ready to eat as muesli. While ground spices are convenient, “whole spices have a longer life and are cheaper, too. Toasting them releases their essential oils and makes them fragrant.” Mandal spreads the likes of cumin, coriander, fennel, cloves or cardamom in a thin layer on a baking tray, and, once the oven’s been turned off, whacks them in for 10 to 15 minutes. “Grind to a powder, then use within a few weeks.”

There are, of course, times when you just need a cookie, and that cooling oven delivers here, too. Grainger suggests following “pretty much any recipe” for the dough, then slicing and transferring it to a lined tray. “Always use a well-insulated pan – a little aluminium tray, for example, isn’t going to hold any heat.” Pop the cookies in the turned-off hot oven for half an hour, and you’ll end up with something “soft, gooey, warm – and perfect for after dinner”.

If you’ve got Pyrex glassware or a metal sieve in need of drying, Mendal recommends doing that in the cooling oven, too; the same goes for plates or dishes that need warming. When cooking for friends, Adriann Ramirez, pastry chef at Finks in London, recommends “sticking in plates or, if I’m serving a sauce, a ceramic bowl once the oven is off, so they’re warmed gently”.

All that said, it’s also worth considering how best to use the oven when it’s actually on, too. Don’t roast or bake a single item; instead, fill it up. “Put all your slow cooks in at the same time and get a week’s worth done at once,” Grainger suggests. Yes, that requires an element of forward-planning, but batch-cooking and freezing is a no-brainer. “Becoming best friends with your freezer is the game to play right now.”

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