Handful of fresh thyme, leaves stripped from the stalk
Preheat the oven to 200C/180C fan/gas 6. On a lightly floured baking sheet unroll the puff pastry sheet, with the back of a knife lightly score a 2cm border around the edge. Use a fork to prick the centre of the rectangle all over, so only the edges will rise. Cover the centre with a sheet of parchment cut to the same size and weigh down with baking beans or dried
pulses. Bake for 20 minutes, removing the weights for the last 5 minutes.
Meanwhile, whisk the mascarpone to create a smooth spreadable texture and season with salt and pepper. Wrap each of the asparagus spears with a strip of the prosciutto. Spread the mascarpone onto the centre of the puff pastry sheet, top with the cheddar and arrange the prosciutto wrapped asparagus tips on top. Bake for a further 15-20 minutes until the pastry is
golden. Garnish with the thyme leaves