Drain the hearts of palm and lay them out flat on a cutting board. To get the most out of your hearts of palm, you should cut it into quarters. Be gentle with these pieces so that they remain largely intact but not too much!
Rinse and dry the radish, jalapeno, and lime. Thinly slice the radish. Deseed and thinly slice the jalapeno. Halve the lime. Set everything aside.
In a medium bowl, add the black beans (drain and rinse) and diced avocado. Add the juice from half of the lime and a pinch of salt and pepper. Toss well to combine.
Use a medium skillet over medium-high heat, and add 1 cup vegetable oil.
In a medium bowl, whisk together the cornstarch, flour, and ⅔ cup water. Dip each piece of heart of palm in the batter and gently lay it in the hot oil. Work in batches, fry the pieces until they’re crispy, about 3 to 4 minutes per side. Transfer the fried hearts of palm to a paper towel-lined plate, and sprinkle with salt.
Wrap the corn tortillas in foil or a dish towel and warm them in the heated oven for about 5 minutes. Cut the remaining half lime into wedges.
To build your tacos, divide the crispy hearts of palm between your tortillas and top them with cabbage, sliced radishes, and jalapenos.
Finish your tacos off with a drizzle of the chipotle.
Serve the crispy hearts of palm tacos with the lime wedges and avocado black bean salad on the side.