On a large serving plate, layer the tomato and melon slices.
Drizzle with olive oil, the brine from the Quick-Pickled Shallots, and the sherry vinegar. Sprinkle salt and pepper to taste.
Evenly distribute the Quick-Pickled Shallots, and top with crumbled feta. Add chile flakes, if desired. Finish with fresh basil and mint, and edible flowers if desired.
Enjoy immediately. Salad is best eaten right away, but keeps well overnight in the fridge. If you want to prepare it ahead of time, save the fresh herbs and flowers to garnish just before you serve.