Using a food processor, finely chop the onion, carrots, garlic, and sunflower seeds then transfer to a large bowl. (I prefer to process each ingredient individually to achieve the best texture.)
Next add the cooked lentils to the food processor and pulse until they appear slightly pureed, then transfer them to the bowl as well. *Be careful not to over process the lentils. You don’t want them to turn to mush--there should still be some shape to at least half of them.
Once you have all of the vegetables, lentils, nuts and seeds in the bowl, add the sweet potato, breadcrumbs, herbs/paprika/salt&pepper, and the flax meal then stir everything together.
Next pour in the barbeque sauce and the egg and stir until well-combined. Sprinkle in the flour a little at a time as you continue to stir. If the mixture seems too wet, add more flour as needed.
Form eight individual patties with your hands, making sure to keep them somewhat flat with rounded edges and somewhat smaller than the bun. They will hold together better if they aren’t too thick or too big.
When you’re ready to cook them, start by warming the olive oil over medium-heat in a skillet for at least five minutes. Once the skillet is thoroughly heated, cook the burgers on each side for about 5-6 minutes.