Step 1

For the labne, place a medium sieve over a large bowl; line with muslin or a clean dish cloth. Spoon yoghurt onto muslin. Gather corners of cloth; secure tightly with string or a rubber band. Place a can on top to act as a weight. Refrigerate for 24 hours.

Step 2

For the sumac onions, combine onion, sumac, lemon juice and salt flakes in a small bowl. Set aside until ready to serve.

Step 3

To make preserved lemon dressing, place ingredients in a screw-top jar; shake well. Season to taste.

Step 4

Process 150g of the fetta until smooth. Add labne; process until just smooth. Season.

Step 5

Spread labne mixture over the base of a large platter or bowl. Top with watermelon, cucumber and radishes. Top with drained onions, crumbled remaining fetta, pistachios and herbs. Drizzle with dressing.