Preheat oven to 400F (200C). Line a rimmed baking sheet with parchment paper.
Thinly slice hearts of palm lengthwise; cut slices crosswise into 3/4-inch lengths. Transfer to a medium bowl and, using fingers, gently press and break apart into shreds.
In another medium bowl, whisk together mayonnaise, Old Bay seasoning, salt and pepper until well blended. Stir in hearts of palm and green onions until well combined (I like to get my hands in, to further break up hearts of palm).
Sprinkle half the panko over hearts of palm mixture and mix in thoroughly (do not mash). Form into fourteen 1.2-inch thick patties (I used a #40 cookie scoop to portion).
Spread the remaining panko in a small dish. Dredge patties in panko, pressing gently to adhere. As they are dredged, place patties on prepared baking sheet, spacing them evenly. Spray with cooking spray. Discard any excess panko.
Bake for 18 to 22 minutes until light golden brown.
Turn on broiler to HIGH. Broil for 30 to 90 seconds (keep checking, it happens fast!) until deep golden brown. Serve immediately with suggested accompaniments, as desired.
14 Crab Cakes
1 can (14 to 15 ounces) hearts of palm, drained and rinsed
1/4 cup vegan mayonnaise
1 teaspoon Old Bay or other seafood seasoning
1/8 teaspoon fine sea salt
1/8 teaspoon freshly cracked black pepper
1/4 cup finely chopped green onions
1 cup gluten-free panko (Japanese bread crumbs), divided
Chopped fresh parsley