How to roast vegetables

Wondering how to roast vegetables? There's a lot of variation in what different veggies require for the perfect roast; here's how to roast everything from potatoes to aubergines

how to roast vegetables
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How to roast vegetables, you ask? The answer very much depends on the type of vegetable you're about to roast. There's quite a bit of a difference between roasting potatoes and an aubergine, for instance, with different cooking times and amounts of oil needed. 

Which isn't to say you can't roast lots of different veggies in the same roasting tin – you'll just need to add them in at different times. Some vegetables are best pre-boiled before roasting (more on that below), but the general rule applies to all of them: you'll need ample quantities of oil, preferably rapeseed or olive, for a successful roast. The oven is a very dry place, so you'll want to make sure your vegetables don't dry out or burn in it. 

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How to roast vegetables: potatoes and squash

The Sunday roast classic comes out best when pre-boiled. Quarter your roasting potatoes and boil them for five to 10 minutes before placing in the roasting tray. Season and drizzle with oil abundantly. Roast for 40 minutes to an hour depending on your oven, at 220ºC/gas mark 6. 

Sweet potatoes or squash also require pre-boiling for about 10 minutes, and will take even longer to roast (at least a full hour), with even more oil.

How to roast vegetables: carrot and parsnip

Carrots and parsnips are very similar in their roasting requirements: simply halve the carrots, keep the parsnips whole, and put them in about 10 minutes after the potatoes. Drizzle with oil and season abundantly.

Tip: Carrots and parsnips roast and taste much, much nicer when peeled. It really pays to do the little extra prep beforehand. 

How to roast vegetables: broccoli, cauliflower, courgette, peppers

These vegetables are far more tender than root veggies and don't require as much cooking time. Add them in the last 10 to fifteen minutes of roasting, tucking them in between the roots. Drizzle lightly with oil, but not too much. The same method applies to tomatoes. 

How to roast vegetables: aubergine

Notoriously difficult to roast, aubergines have a sponge-like texture that needs a lot of added moisture not to dry out. We recommend roasting aubergines separately from other vegetables, in a shallow roasting tray, covered in tinned tomato and oil, with plenty of seasoning.

You can also try pre-frying aubergine slices in some oil before transferring to the oven. Roast this vegetable for at least half an hour, but it's likely to need a bit longer. When it's soft and green all the way through, it's done.

How to roast vegetables: onion and garlic

Roast garlic and onion can impart a wonderful aroma to your roast vegetable tray, but it's very important not to burn them, or you'll get an acrid taste that's quite unpleasant.

Always tuck your onion and garlic well beneath the surface of the tray to avoid browning. If you do like your onions a little charred, put them in later, in the last 20 minutes of roasting or so. 

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