Heat 1 tablespoon of oil in a frying pan over medium heat and gently soften the chopped brown onions until translucent and fragrant, about 5 to 7 minutes.

Crumble the halloumi into small pieces and add to a mixing bowl alongside the chicken mince.

Finely chop the baby spinach and then add to the bowl with the chicken and halloumi.

Once the onions are softened, allow them to cool slightly before mixing them thoroughly into the filling mixture.

Roll out the puff pastry on a clean surface and divide the filling evenly along one edge. Carefully roll the pastry over the filling to form sausage rolls, sealing the edges well.

Place the sausage rolls onto a lined baking tray and bake in a preheated oven at 180°C for 15 to 20 minutes, or until the pastry is golden and cooked through.

Serve the sausage rolls warm.