Cook the quinoa according to the instructions on the package. Use vegetable broth instead of water. Set aside.
Rinse and drain the chickpeas. Mash with a fork. Leave some of the chickpeas still intact for texture.
In a large pan, heat some oil and sauté the onions for about 2 minutes. Add the garlic and cook for another minute. Then add the red bell pepper, the celery, the mushrooms, and the carrots and cook for about 3-4 minutes.
In a large bowl combine the quinoa, the mashed chickpeas, the flax egg, and the cooked veggies. Add the spices, the mustard, guar gum, salt, pepper, and if using the liquid smoke and red pepper flakes and stir well.
Form 4 patties and heat some oil in a large pan. Cook the patties for about 3 minutes on each side until golden. Serve on whole wheat buns and top them off with tomatoes, avocados, lettuce, BBQ sauce, and mustard.