Preheat oven to 350 F (if baking). In a large skillet, sauté onions and garlic in 1/2 tbsp oil. Mix your flax (egg substitution) together in a small bowl and set aside for at least 10 mins while you prepare the rest of the ingredients.
Place all ingredients (except spices and salt) into a large mixing bowl and stir very well. Now, add seasonings and salt to taste.
With slightly wet hands, shape dough into patties. Pack dough tightly as this will help it stick together.
Cooking methods: You can cook the burgers in a bit of oil on a skillet over medium heat for about 5 minutes on each side. If baking, do so for 25-30 mins (15-17 minutes on each side) at 350 F, until golden and crisp. For the BBQ, pre-bake the burgers for about 15 minutes in oven before placing on a pre-heated grill until golden and crisp on each side.