In a large frying pan, heat 1 tablespoon of olive oil over medium heat. Add the onion, garlic, and grated carrot. Cook, stirring often for 5-8 minutes, or until soft and fragrant and starting to brown. Do not let the mixture burn.

In a large bowl, combine the drained black beans, cooked quinoa, ground flax, sautéed onion mixture, and the rest of the ingredients. (After transferring the onion mixture to the bowl, wipe down the skillet with a clean paper towel so you can use it to cook the burgers).

Mash the ingredients using a fork, mojito muddler, or potato masher, focusing on crushing the black beans. Mix and mash until everything is sticky and holds together. Alternatively, you can pulse the mixture in a food processor several times until a thick dough forms. Make sure not to over-process because you want to leave some texture to the bean and quinoa mixture.

Wet your hands in cold water or spread a tiny bit of olive oil on your hands (to keep the dough from sticking to your hands) and form the bean mixture into 4-6 patties (4 large burgers, or 6 smaller patties).

Place the patties on parchment paper on a cutting board, or spray a plate with olive oil. Chill in the fridge for at least 20 minutes. This step is optional, but it helps make the burgers crisp and keeps them from falling apart while cooking.

Heat 1 tablespoon olive oil in a large pan over medium heat. Cook the patties for 3-4 minutes per side, or until browned and crispy on the outside and heated through. Serve hot on buns with your favorite toppings. Try the garlicky yogurt sauce in the notes!