Preheat the oven to 180°C (or prepare your air fryer).
If the sweet potatoes aren’t organic, peel them. Cut each into 6–8 long wedges.
Peel and cut the red onion into wedges.
Place the sweet potatoes and onions on a baking tray (or in the air fryer basket). Drizzle or spray lightly with olive oil and season with salt and pepper.
Bake or air fry for about 15 minutes, until the sweet potatoes are golden and tender.
Scatter the minced garlic over the vegetables, then crumble the Stilton on top.
Return to the oven (or air fryer) for another 3–5 minutes, just until the cheese has melted and starts to bubble.
Serve warm.