In a small mixing bowl, add the yellow squash, julienned zucchini and grape tomatoes. Splash with some olive oil and vinegar, and season with salt. Let sit for about 5 minutes.
With your sharpest knife, slice the scallops equatorially into 1/4-inch, or thinner, rounds.
Prep your salt block by coating it with a little olive oil. Lay the planks of zucchini across the block; these will block the absorption of too much salt into the scallops.
Arrange the scallop slices, slightly overlapping each other, in four rows, with half of each round sitting on top of the zucchini and the other half directly on the salt block. Add a squeeze of lemon juice and drizzle a few drops of olive oil on each row of scallops.
Top the scallops with some of the vegetable salad and the basil leaves. Serve.
Consumption of raw or undercooked eggs, shellfish and meat may increase the risk of foodborne illness.