In a nonstick pan, dry-toast the walnuts on medium heat, tossing and flipping them for about four minutes. Remove from heat and place in the bowl of a food processor. Add the oats, tomato paste, tahini, cajun spice blend, sea salt, worchestershire sauce, and liquid smoke. Process, scraping the bowl down as needed until crumbly but holds together after giving it a squeeze in your fist. Add 1/2 the chickpeas, and 1/2 the rice. Set aside. In a large mixing bowl, add the remaining 1/2 of the chickpeas and rice and mash together using a potato masher just a few times to soften (we still want chunks here). Set aside.
Heat the coconut oil in a pan on medium. When shimmering, add the diced mushrooms and cook on medium low for about 6 minutes tossing and flipping just a few times - we want a good sear on the mushrooms. Add the onion and bell pepper to the pan and saute for about 8-9 minutes on medium low heat, flipping and turning occasionally. A bit of charring is okay. Remove from heat and spoon 1/2 of the mushroom mixture in the food processor while adding the remaining to the large mixing bowl with the chickpeas and rice. Process the ingredients in the food processor, pulsing, and stopping to scrape down and redistribute the ingredients in the bowl several times. There still should be some chunks, but all the ingredients will be incorporated. Into the large mixing bowl, add the processed bean/spice/mushroom mixture. Using your hands, mix throughly squeezing and pushing the mixture together. Now is a good time to taste test the mixture. If you want more heat, add a douse or two of Tabasco or even more Cajun seasoning!
Divide the mixture into 5 patties (about 1/2 C or 140g each) or 7 patties (about 1/3 C or 95g each) by shaping them into round balls tucking in any large pieces of veggies that may be hanging out on the sides. Using your hand or the back of a metal measuring cup, press each ball into a patty using gentle pressure to about 1/4"- 1/2" (.6 - 1.2 cm) thick. Gently nudge back into shape if needed.
Place the patties flat on a parchment lined sheet pan in refrigerator for at least one hour. If freezing, slide the pan in the freezer for one hour then stack them between pieces of parchment paper and into a freezer bag for longer storage.*** Now is a good time to get the jalapeño aioli going (see below).
FOR COOKING - two options: *Pan frying yields a bit of charring and crispy edges on the burgers. It's quicker then baking. Baking will dry the patties out a bit more than pan frying, but less oil is used. They also take longer to cook. A. TO BAKE: Preheat oven to 425F (218C). Line a sheet pan with parchment paper or use a silpat. Brush a layer of coconut oil on the parchment paper and lay a patty on top of it. Brush the top with more coconut oil. Repeat on the remaining patties. Bake each side for 15 minutes. Sprinkle with sea salt. To keep warm, turn the oven off, prop the door open and rest the patties in the oven.B. TO PAN FRY: Preheat the oven to 200F (95C) and line a sheet-pan with parchment paper. Place the pan in the oven. This will keep the patties warm after they're cooked.Add two to three Tbs of coconut oil to a cast iron skillet on medium heat. Heat until shimmering. Add three patties. Be sure to give them plenty of room. Cook for about 4 minutes on each side, being careful when flipping the patty. Slide the patty on the parchment lined sheet pan in the oven. Sprinkle with sea salt. Finish cooking the remaining patties adding more oil as needed.
Store cooked patties in a lidded container for up to three days in the refrigerator, or stack the patties between pieces of parchment paper and slide into a freezer bag for longer storage. Freeze for up to two weeks.