Drain canned chickpeas from can with a strainer, rinse well with cold water. (If using dry beans please read the note below.)
Chop onion, garlic and mushrooms finely.
Using a food processor or a cheese grater, finely grate a beet. Then chop up even finer. Ideally less than 1/4 inch a piece.
If walnuts are whole, halves or pieces, crush them into small pieces.
Mix flaxseed meal and water to create an egg replacer. ( If you are not vegan, use 1 egg )
Mash chickpeas with a food processor, mortar and pestle or fork.
Heat up a pan and add a tablespoon of olive oil then cumin seeds.
Add onion, garlic and mushroom into the pan, sprinkle a pinch of salt and sauté until they are deeply brown.
Add turmeric powder, coriander seeds powder and red chili powder and cook for a minute.
Combine walnut meal and beet and mix throughly. Turn off the heat and put aside.
In a medium size bowl, combine mashed chickpeas and the concoction above.
Add the egg replacer ( flaxseed meal + water ) and all purpose flour.
Season with salt and pepper. Add chopped coriander leaves.
Mix thoroughly with hands.
Once well combined, it is a good time to take a small piece to taste to adjust flavor.
If you like small patties, divide the mixture into 6 else into 4. Shape into discs and place them onto a baking sheet lined with a parchment paper or silicon mat.
Refrigerate for 30 minutes so that they retain shape when baked and all the flavors get combined.
While burgers are resting, make BBQ sauce. Ingredients and instructions are below.
After refrigerated for 25 minutes, preheat the oven for 375F (190C).
When oven reaches 375F transfer burgers from a refrigerator to oven. Bake for 30 minutes.
If the oven has broiler, leave the burgers alone for 30 minutes then broil for 3-5 minutes, depending on your preference.
If the oven does not have broiler, carefully flip burgers after 15minutes so that both sides cooks evenly.
Take them out from oven and garnish as you like.