Toast pistachios in a frying pan over low-medium heat for a few minutes. Remove from heat and crush in a mortar and pestle. Set aside.
Place watermelon wedges on a baking sheet. Top each wedge with cheese shavings and thyme leaves. Place under a hot grill for about 5-8 minutes until cheese melts and starts to turn golden. Alternatively, toast cheese with a kitchen blowtorch.
Sprinkle the nut crumble over the watermelon triangles. Season with salt and pepper. Serve on a cheese board with sprigs of thyme.
Notes
Make sure you use a perfectly ripe watermelon, red and sweet.If stronger cheese is not to your liking, mozzarella cheese or bocconcini balls work well for grilling/melting.