In a food processor add 1 can chickpeas, 4-5 sticks hearts of palm, 2 Tbsp plant mayonnaise, ½ rib celery, ¼ red onion, 1 Tbsp capers, ½ Tbsp dijion mustard, ½ fresh lemon, ¼ cup fresh parsley, and salt. Pulse for a few seconds until everything seems well mixed. Be careful not to over process, you want a little texture.
Give the mixture a taste and make any adjustments you'd like.
You can place the mixture into an airtight container in the fridge while you prepare the tomatoes, this also allows for the flavors to develop.
Wash and dry your tomatoes. Using a pairing knife at a 45 degree angle, cut the tops of the tomatoes off. Similarly to how you would a pumpkin for carving.
Use a spoon to scoop out the insides, then take the "tuna" mixture and fill each tomato. Serve cold.