- STEP 1
Preheat the oven to 200 degrees Celsius / 180 degrees fan / gas mark 6.
- STEP 2
Line a baking tray with greaseproof paper. Heat a frying pan over a medium heat.
- STEP 3
Add the shallots and asparagus tips to a bowl and toss in the oil and cook for 3 minutes in the pan until softening and browning. Remove the asparagus if it cooks quicker than the shallots.
- STEP 4
Add the balsamic vinegar and allow it to bubble and coat the shallots and asparagus. Set aside to cool.
- STEP 5
Unroll the pastry and put on the tray. Using a sharp knife, score a 2.5 cm border around the pastry edges and prick the middle with a fork several times.
- STEP 6
Spoon the mixture on inside the border and top with the cheese.
- STEP 7
Brush the edges with the egg and bake for 15-20 minutes.