1.To make dressing, combine juice, the water, mustard and oil in a small jug. Season to taste.
2.Combine celery, salad leaves, apple and trout in a large bowl; drizzle with dressing, toss gently.
3.To serve, sprinkle salad with rind; accompany with sourdough.
Use a zesting tool to remove the rind from the lemon. Replace the lemon juice and rind with orange for a sweeter, more subtle citrus flavour. We used red witlof for added colour, but use your favourite salad mix. Use hot-smoked salmon or shredded barbecued chicken breast as an alternative. Freeze any leftover sourdough to use in future recipes.