These are the same vegan crab cakes that I made on the Today Show last year. They'll also be in my upcoming cookbook (Penguin Random House 2018), so you know they're good. Stock up on cans or jars of hearts of palm because you're going to want to make this often. Ume plum vinegar is a tangy briny Japanese condiment. Find it at health food stores (around $3.50) or online. An okay sub for it would be apple cider vinegar or lemon juice. To make gluten free you can use gf panko. Add a minced jalapeño pepper when you combine the ingredients for a little more heat.