Step 1 To make salad, heat half the oil in a large frying pan. Add onions and celery. Cook over a low heat for 5 minutes or until soft. Add cumin. Cook for 1 minute. Add lentils and lemon juice. Stir for 1-2 minutes until juice evaporates.

Step 2 Add stock and currants. Bring to the boil then reduce heat to low and simmer uncovered for 10-15 minutes or until all liquid is absorbed. Cool then fold through courgettes and coriander.

Step 3 Meanwhile, heat a grill pan or barbecue to high. Thread fish and prawns onto skewers and spray with oil. Place asparagus and skewers on grill and cook for 6 minutes, turning occasionally. Serve lentil salad with skewers and asparagus.