Oil and line a swiss roll tin (ours was 31cm x 23cm) with baking parchment. Put a large saucepan over a medium heat, pour in the olive oil and stock, bring to a simmer, then pour in the polenta, stirring constantly. Cook for 10-15 mins until thick and coming away from the side of the pan.

Remove from the heat and stir in the cheese and butter. Once melted, pour into the prepared swiss roll tin. Leave to cool for 1 hr, then cut into 16-24 pieces. Will keep chilled for up to three days.

Lay the polenta pieces in your air fryer tray in a single layer, then cook at 200C for 15-20 mins until golden. Will keep for a day in an airtight container. Add the topping of choice (see recipes above under 'Complete the dish').