Roasting Peppers and Preserving Them in Oil

Why a Jar of Roasted Peppers Earns Its Fridge Space

A roasted pepper is a small piece of kitchen alchemy. Raw, it is crunchy, a little grassy and faintly bitter. Ten or fifteen minutes over a flame and it slumps into something sweet, silky and gently smoky, with a depth that no raw pepper quite manages. Make a batch while they are cheap and plentiful — late summer, or a glut from the greenhouse — and you have the makings of a dozen better meals. Piled onto toast, folded through pasta, laid over grilled fish, chopped into a dressing, they lift plain cooking without any fuss at all.

Preserving them in oil is one of the oldest ways of holding on to a harvest: char the vegetables, pack them down, cover them with good oil and let the fridge do the rest. It takes about an hour, most of it unattended, and the jar will keep for a fortnight. It also happens to be the sort of thing that makes you look like a far more capable cook than you probably are.

Choosing Peppers — and Growing a Few of Your Own

Red and yellow bell peppers are the standard, but the long, pointed varieties — often sold as Romano or frying peppers — are sweeter, thinner-skinned and roast far better. If you grow your own, those are the ones worth seeking out. In the UK they do best under glass: sow indoors in late January or February, pot on steadily, and plant into a greenhouse, polytunnel or a sheltered south-facing wall once nights are reliably above 10°C. They want steady watering rather than a soaking, and a feed once the first flowers set.

Peppers are slow. Fruit will colour from late summer into early autumn, and the flavour improves dramatically the longer you leave it on the plant. Pick when the skin is glossy and fully coloured; dull, wrinkled peppers will roast to nothing. If you have a glut, roast in batches and freeze in portions rather than letting them soften on the windowsill.

Charring Them Properly

There are three sensible methods, and all of them work. Choose by how much smoke you can tolerate and how many peppers you have.

• Gas hob: sit the peppers directly on the burner over a medium-high flame. Turn with tongs every few minutes until the skins are blackened in patches and the flesh has collapsed — roughly 10 to 15 minutes. Best flavour, most smoke.
• Grill: halve and flatten the peppers, lay them skin-side up on a tray and place about 10cm below a hot element. They will blister and blacken in 10 to 12 minutes. Quicker and tidier.
• Oven: whole or halved at 220°C, turning once, for 30 to 40 minutes. Less smoky and easiest for large quantities, though the flavour is milder.

Don't be timid about the black. That char is where the smoke and sweetness come from. But equally, don't reduce them to ash: the flesh under the skin needs to be soft right through, or peeling becomes a misery.

Sweating and Peeling

As each pepper finishes, tip it into a bowl and cover the bowl tightly with a plate or a sheet of cling film. Leave for 15 minutes. The trapped steam loosens the skins so they slip away with almost no effort. This step is not optional — peeling hot peppers immediately is fiddly and wasteful.

Then peel with your fingers or a small knife, working over the bowl so you catch the juices. That liquid is far too good to lose; add it back to the jar or whisk it into a dressing. Do not rinse the peeled peppers under the tap, however tempting — you will wash away the sugars you have just coaxed out. Scrape away the seeds and pale pith with the back of a knife and discard the skins, stems and seeds.

Packing Them in Oil with Garlic

Sterilise a jar: wash it in hot soapy water, rinse, then dry it in a low oven at 120°C for 15 minutes. Let it cool completely before filling. Layer the pepper pieces into the jar, scattering a pinch of fine salt, a few slivers of garlic (two or three cloves per 500ml jar), a strip or two of lemon zest, some thyme or oregano and a few black peppercorns as you go. Press down gently to push out trapped air.

Cover completely with olive oil — a mild, fruity oil rather than your best peppery bottle. Everything must sit beneath the surface; any exposed pepper will mould. Tap the jar on the worktop to bring bubbles up, then top up again. A little lemon juice or vinegar in the mix helps keep things stable.

A word on safety: garlic and peppers in oil create the oxygen-free conditions that Clostridium botulinum likes. Keep the jar in the fridge at all times, always use a clean fork to lift pieces out, and eat it within two weeks. If you would rather not worry, leave the garlic out of the jar and add it fresh when you serve, or freeze the peppers in small oil-covered portions.

What to Do with the Jar

This is the sort of thing that quietly improves the whole week. Try them:

• On hot toast rubbed with a cut clove of garlic, with a little salt.
• Torn into a bowl of white beans or chickpeas with plenty of the oil.
• Folded through pasta with anchovy, chilli and a squeeze of lemon.
• Layered into a sandwich with mozzarella and basil.
• Chopped small and stirred through a vinaigrette or a bowl of mayonnaise.
• Laid over grilled fish, or alongside feta with mint and a drizzle of the jar oil.

And don't tip that oil away when the peppers are gone. It is now pepper-and-garlic infused, and it makes a fine dressing or a base for frying eggs. A jar of these in the fridge is a small, practical piece of sunshine — worth the hour, every time.