Toss them in a bowl with 1 tbsp olive oil, 1 tsp coarse salt, ½ tsp freshly ground black pepper and 1 tsp fresh thyme or rosemary and 1 clove garlic (optional).
Preheat & arrange
Preheat the air fryer for 5 min at 180 °C.
Place the beetroot in the basket in a single layer or slightly overlapping with air in between.
Main roasting
Roast at 180 °C for 18–25 min, turn/shake halfway.Start the kitchen timer here
Check tenderness with a skewer: it should glide through with slight resistance.
Glazing (optional)
Drizzle 1 tsp balsamic vinegar or lemon juice over and give 1 minute extra in the air fryer.
Serving
Optionally sprinkle with 30 g toasted hazelnuts /seeds and a little extra flaky salt.
Serve immediately – warm or lukewarm.
Video
Notes
Whole beetroot: Small whole ones (4–5 cm) take about 35–45 min at 180 °C; prick them with a skewer and turn halfway.Colour: Use gloves/a cutting board that can handle staining.Taste: Acidity at the end balances the sweetness – don't skip it.