Salmon and Asparagus Wraps with Rocket Pesto

Farmed salmon has become much better quality over the years and in my opinion some of the best available comes from Ireland, where the sea is always freezing cold and for the most part is unpolluted, with strong tidal flows. Make sure your salmon fillets are all even-sized and about 2.5cm (1in) thick to ensure even cooking. They also work well on the barbecue and can be made up to 12 hours in advance, covered with clingfilm and chilled until needed – just don’t add the squeeze of lemon juic