Make the flax egg by combining the ground seed with water; let sit 3-4 minutes until it's a gel.
Sauté the onion and garlic until the onions are soft.
Add all the remaining ingredients to a food processor and pulse until the ingredients are combined and the chickpeas are chopped. Don't over-chop. It's OK if some chickpeas are still whole. The mixture should be chunky.
Using your hands, form patties.
In a non-stick pan, brown each patty about 4 minutes per side until crisp.
Or, place on a baking sheet and cook at 400° for 20 minutes, flipping half-way through.