Vegetables are the unfinished homework for a lot of people starting out with an air fryer: they cook in less time than in the oven, yes, but they also overcook with alarming ease. Here's how I handle broccoli, zucchini and asparagus, what to look for so you don't serve them limp, and how to get them ready for several days of meal prep.

Before going on, a warning I always repeat: the times and temperatures I give are approximate. They depend on the air fryer model (not all heat the same or have the same power), the amount you put in the basket and the thickness of the pieces. If it's your first time with a particular vegetable, start with the short time, open the basket, check and add minutes if needed. It's better to poke twice than to eat charcoal.

For this batch you need:

• 1 medium head of broccoli, cut into florets of similar size (important: if you mix large and small florets, the small ones will burn before the big one is done).
• 1 medium zucchini, in slices a little under a finger thick or in half-moons.
• 1 bunch of green asparagus, with the woody part of the stem removed.
• Extra virgin olive oil (a level tablespoon for the whole batch is usually enough; the idea is to coat, not drench).
• Salt and whatever you like for flavour: black pepper, garlic powder, paprika, lemon, dried herbs.
• A large bowl for mixing and, if you have them, kitchen tongs to stir halfway through cooking.

You don't need parchment paper or a special rack for most baskets, but if your basket has large holes, a perforated tray helps keep small pieces from falling through.

Wash the vegetables and dry them with a cloth or paper towel. Moisture is the enemy of roasting: if they go in wet, they steam instead of browning. This step, which seems trivial, is the one that changes the result most.

In a bowl, toss the vegetables with a drizzle of oil and the salt. Spread it around well with your hands so every piece is shiny but not dripping. If you overdo the oil, the broccoli will smoke and smell like a fryer; if you use too little, it will dry out.

Each vegetable has its own pace. I make them separately or, at the very least, start with the one that takes longest:

• Broccoli: 180 °C (350 °F) for about 8-10 minutes, shaking the basket halfway. Medium florets. If they're very thick, add 2-3 minutes; if they're thin, check them sooner.
• Zucchini: 180-190 °C (350-375 °F) for about 10-12 minutes in slices a little under a finger thick. Here thickness rules: a thin slice dries out in four minutes and a thick one may need 15. Check from minute 8.
• Asparagus: 190-200 °C (375-400 °F) for about 6-9 minutes, depending on the thickness of the stem. Thin ones cook very fast; thick ones hold up longer. They're ready when the stem gives when poked but the tip isn't scorched.

Shake the basket halfway through cooking in every case. Don't fill more than two thirds of the basket: if you stack, the top doesn't brown and the bottom overcooks.

Take out one piece, poke it or taste it. If it's hard, put it back for 1-2 minutes. If it's already tender, take it out immediately: inside the air fryer, with the residual heat, it keeps cooking. This is the most common mistake with air fryer vegetables.

• Cut pieces the same size. It's the golden rule. It doesn't matter what time you set if you mix thicknesses.
• Preheat if your model allows it or the manufacturer recommends it. It helps the browning be more even.
• Don't crowd. Better two quick batches than one full one that comes out uneven.
• Season at the end if you use lemon or vinegar. Acids before cooking can dry out the vegetable; a squeeze of lemon right out of the basket is much better.
• Take advantage for meal prep. You can cook the broccoli and asparagus in batches and store them in containers in the fridge for 2-3 days. Zucchini holds up worse: I make it the same day or leave it for the next day at most.

• Putting the vegetables in wet. They steam, don't brown, and on top of that they spatter.
• Too much oil. You don't need more than a drizzle; excess creates smoke and a fried taste.
• Filling the basket to the top. The hot air has to circulate; otherwise there's no toasting.
• Not shaking halfway. Pieces touching the rack toast more than those on top.
• Trusting someone else's time. Your air fryer isn't mine. The minutes I give are a starting point, not a foolproof recipe.
• Leaving them inside when done. Residual heat overcooks them in a couple of minutes.

The times and temperatures in this article are approximate and depend on the air fryer model, the amount of vegetables and the thickness of the pieces. Always adjust to your appliance and check for doneness by poking or tasting the vegetable. I don't include nutritional figures or health recommendations because I don't have a public source to back them in this text; if you need that kind of data, check official sources or a professional.

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