Place the walnuts in a food processor and process until ground into a meal. Empty walnuts into a large mixing bowl. Then place tempeh and chickpeas into the food processor and pulse until crumbly. Add into the same bowl with the walnuts, along with the flax egg, onion and garlic.
Place the beets, barbecue sauce, Dijon mustard, soy sauce and hot sauce in the food processor and run until smooth. Pour the beet mixture over the walnut mixture in the large bowl. Add the cumin, paprika, salt and pepper. Stir to combine.
Preheat the oven to 375º F and line a baking sheet with parchment paper.
Using a ½ cup measure, divide the mixture into 6 equal patties. Place patties on baking sheet and bake for 30 minutes or until crispy around the edges.
Serve on buns with tomato, vegan cheese, vegan mayo, pickles, lettuce and mustard. Add or subtract any other toppings you choose!