Place the quinoa in a small saucepan along with 1 cup of water. Bring the water to a boil then reduce heat to medium low and cover the pan. Cook 10-15 minutes until the water is absorbed and quinoa is cooked. Remove from heat.
Heat the oil in a small sauté pan over medium heat and add the onion and garlic. Sauté until onions are softened, 5-6 minutes. Place the mixture in a large bowl. Add approximately 1½ cans of black beans to the bowl and using a potato masher or fork, mash all of the ingredients together until a pasty mixture forms.
Stir in the remaining beans along with the tomato paste, egg, corn, cilantro, chipotles, cumin and salt. Stir in the cooked quinoa and ground oats until evenly distributed.
Form the mixture into 8 equal patties, compacting them well with your hands as you form them. Place the patties on a baking sheet, cover them with plastic wrap and refrigerate for a few hours or overnight.
To make the yogurt sauce, puree the yogurt, chipotles, adobo sauce, cilantro, lime juice, and honey together in a mini food processor until smooth.
When ready to eat, preheat the oven to 400°F. Spray a baking sheet with olive oil spray and place the patties on the sheet. Cook 10-12 minutes until the patties are golden brown and crispy, then carefully flip the over and cook another 10 minutes. Alternatively, you can pan fry the patties in a skillet with a little olive oil. Serve the patties on the buns with the cilantro yogurt sauce and toppings of your choice.
Nutritional information is for the patties plus sauce.
* To make a flax egg, mix 1 tablespoon ground flaxseed with 3 tablespoons water in a bowl. Let sit for 5 minutes to thicken. Use in recipe in place of 1 egg.