Trim and dry. Snap the stem ends off each bean and pull away any stringy fibres running down the seam. Spread them across a clean tea towel and pat until the skins feel completely dry to the touch — no slickness, no visible droplets.

Preheat the basket. Set your air fryer to 190°C and let it run empty for 3 minutes. You'll hear the fan settle into its steady hum and feel a wave of warm air when you open the drawer. A hot basket gives the beans an instant head start on browning.

Toss with oil and seasoning. In a large mixing bowl, combine the beans, olive oil, garlic powder, smoked paprika, salt and pepper. Use your hands to rub the oil into every bean until they all wear a faint, even sheen. If you're using Parmesan, hold it back for now.

Arrange in a single layer. Tip the beans into the basket and shake gently so they sit in one mostly even layer. A few overlaps are fine, but a deep pile will trap moisture and leave you with limp, pale beans instead of blistered ones.

Air fry for 5 minutes. Cook at 190°C, then pull the drawer out and shake. You're looking for the first patches of darkened, wrinkled skin and a smell of toasted garlic drifting up from the basket.

Shake and continue. Return the basket and cook for another 3–5 minutes. The beans are ready when they're deep green with charred, blistered spots and bend easily without snapping. Thin beans may need only 3 more minutes; fat ones may want 5.

Finish while hot. Slide the beans into a serving bowl and immediately scatter over the Parmesan, lemon zest, lemon juice, flaked almonds, shallot and chilli flakes. Toss once so the cheese melts slightly against the warm skins.

Rest for 2 minutes. Let the bowl sit on the counter briefly before serving. This short pause lets the lemon and garlic settle into the beans rather than sitting on top of them.