Heat sauté pan over medium heat; add oil.

When oil is hot, add onion and salt; sauté for five minutes, until softened. Add garlic, cumin, and smoked paprika. Sauté for two to three minutes. Remove from heat; transfer to a mixing bowl.

Add lentils and feta to the onion mixture, stirring to combine. Add eggs, flour, and panko. Stir to combine; set aside to thicken for 20 minutes.

In a sauté pan over medium heat, heat canola oil.

Form the lentil mixture into patties; fry for five minutes on each side, until cooked through.

Serve on a bun with Spicy Mayo, a slice of tomato, and a sprinkle of feta, if desired.