Over medium-high heat, sauté the onion in a cast-iron skillet in 1 tablespoon of the oil until soft and golden—about 7 minutes. Set aside.
Place the zucchini in a food processor, pulse to a fine dice and remove to a bowl.
Add the carrots to the food processor and pulse, then add the black beans (reserving 1/3 cup for later), jalapeños, garlic and all seasonings. Pulse until the mixture comes together.
Add the oats, flour and corn and pulse until fully combined.
Transfer the mixture to a bowl and combine with the zucchini and onions.
Mash the remaining beans with a potato masher or fork, then combine the beans with the other ingredients by hand.
Shape and form into 6 to 8 patties.
Heat another tablespoon of oil in a large cast-iron skillet over medium heat.
Fry the patties for 5 to 7 minutes, then flip and cook for another 5 to 7 minutes until both sides have a nice crust.