2 tbsp olive oil
1 6-inch rosemary sprig
125ml / 1/2 cup plain whole-milk Greek yogurt
1 tbsp honey
1 1.5kg seedless watermelon, rind removed, cut into 2cm pieces
3 tbsp fresh grapefruit or lemon juice
1 tsp crushed red pepper flakes
1 tsp poppy seeds
Coarse sea salt
Heat oil in a small skillet over medium. Fry rosemary until crisp, about 20 seconds. Transfer to a paper towel to drain; set rosemary oil aside.
Mix yogurt and honey in a small bowl; season with sea salt.
Toss watermelon and grapefruit or lemon juice in a large bowl; season with sea salt.
Spread yogurt on a large platter. Top with watermelon and crumble fried rosemary over. Drizzle 1 tbsp. reserved rosemary oil over (save remaining oil for another use) and sprinkle with red pepper flakes and poppy seeds.