Bring a large pot of water to a boil over high heat and add chayote; simmer until tender, 35 to 45 minutes; peel, seed and cut in 1/4-inch dice. If using a cucumber, simmer until fork-tender, about 20 minutes; peel, cut in half vertically, scoop out seeds and dice. You should have a generous cup of chayote or cucumber.
Combine chayote with tomatoes, onions, dill, salt and 8 turns of pepper in a small bowl. Serve with seafood dishes.
Yield: about 1 2/3 cups