Roast sunflower seeds in a pan without fat, remove. Cut melon in half, remove seeds. Peel the flesh. Halve one half of the melon again crosswise and cut into thin slices.
Wash, clean and slice the tomatoes. Wash the cucumber and slice it finely. Clean, wash and tear lettuce into pieces. Arrange everything on plates. Puree remaining melon meat.
Add oil, vinegar and honey and mix. Season to taste with salt and pepper. Pour some sauce over the salad. Serve the rest extra. Sprinkle salad with sunflower seeds.