These posh pressed sandwiches would make a great addition to any lunchbox or picnic.
Make the pesto by putting the basil leaves in a food processor with the pine nuts, garlic and salt. Process together, then add the Parmesan and process again.
Add the oil and process once more to make a thick, slightly runny paste. Taste, and add a little more salt if you like, or a little more oil to give a runnier texture.
Bake the ciabatta as instructed on the packet and leave to cool. Cut the loaf in half lengthways. Spread the cut sides with the pesto, then distribute the rocket leaves over the base, followed by the ham.
Layer the cheese in slices over the ham, then put the top on the loaf and press down lightly with your hand so that everything sticks together.
Wrap tightly in cling film, foil or greaseproof paper, as snugly as possible. Put the whole thing in the fridge overnight – preferably between two boards or plates with a small weight on top, such as a tin of tomatoes.
Next day, unwrap the sandwich, leaving it on top of the wrapping, and carefully cut it into eight diagonal slices. Rewrap tightly.
Top tip: The sandwiches can be made in individual ciabatta rolls instead of one long one. Wrap them separately and tightly in cling film. As long as this is done firmly, pressing is not essential. You can use a baguette instead of the ciabatta, but it makes more crumbs and is harder to chew.
1 part-baked ciabatta loaf
3-4 tbsp Pesto Genovese (see below for the recipe)