Cut your onions in half, and slice them.
Warm up your oil in a pan to medium heat, and add your onions.
Cook your onions until they completely caramelise. If they seem like they're burning, add a little bit of hot water and continue cooking until done.
In a food processor, put your tofu, flax eggs, salt and pepper.
Shape up your patties. This will give you exactly 4 patties.
Cook your patties on a non stick pan on medium-high heat, until golden brown (about 3-4 minutes on each side).
While your patties are cooking, make sure your buns are toasted to perfection.
Assemble your burger, by adding a teaspoon of dijonnaise, some crunchy greens of your choice, your patty, caramelised onions, and a generous dollop of dijonnaise.