Preparation Mince garlic and mash to a paste with 1/2 teaspoon salt using side of a large heavy knife. Whisk together lime juice, oil, and garlic paste in a large bowl, then add onion, tossing to coat. Halve chayotes lengthwise, then peel with a vegetable peeler and scoop out pits with a spoon. Cut chayotes crosswise into 1/3-inch-thick slices, then halve slices lengthwise to make 1/3-inch-thick sticks (sticks will not be uniform). Cook chayotes in a 4- to 6-quart pot of boiling salted water until crisp-tender, about 6 minutes. Drain well in a colander, then, while still hot, toss with dressing. Cool to room temperature. Cut hearts of palm diagonally into 1/4-inch-thick slices, then add to chayote mixture along with celery, parsley, cilantro, and remaining 1/4 teaspoon salt. Gently toss. Cooks' note:Salad, without herbs, can be made 3 hours ahead and chilled, covered. Bring to room temperature and stir in herbs before serving.
Preparation Mince garlic and mash to a paste with 1/2 teaspoon salt using side of a large heavy knife. Whisk together lime juice, oil, and garlic paste in a large bowl, then add onion, tossing to coat. Halve chayotes lengthwise, then peel with a vegetable peeler and scoop out pits with a spoon. Cut chayotes crosswise into 1/3-inch-thick slices, then halve slices lengthwise to make 1/3-inch-thick sticks (sticks will not be uniform). Cook chayotes in a 4- to 6-quart pot of boiling salted water until crisp-tender, about 6 minutes. Drain well in a colander, then, while still hot, toss with dressing. Cool to room temperature. Cut hearts of palm diagonally into 1/4-inch-thick slices, then add to chayote mixture along with celery, parsley, cilantro, and remaining 1/4 teaspoon salt. Gently toss. Cooks' note:Salad, without herbs, can be made 3 hours ahead and chilled, covered. Bring to room temperature and stir in herbs before serving.