Jenn Louis uses whatever melon looks best at the market, and she sometimes swaps out the feta for ricotta salata, or the chives for mint.
In a small bowl, combine the olive oil, lemon juice, shallot, preserved lemon and crushed red pepper and season with salt and pepper.
Arrange the melon slices and blackberries on a platter. Drizzle the dressing over the fruit. Garnish the salad with the feta and snipped chives and serve.