Make the quinoa: Rinse the quinoa in cold water in a saucepan, swirling it with your hand until any dry husks rise to the surface. Drain the quinoa as well as you can and then put the saucepan on the stovetop to dry and toast the quinoa. Turn the heat to medium-high and shake the pan regularly until you see the quinoa moving easily and can hear the seeds moving in the pan, indicating that they are dry. Add the water, salt and pepper. Bring the liquid to a boil and then reduce the heat to low or medium-low. You should just see a few bubbles, not a boil. Cover with a lid, leaving it askew (or if you have pour spouts, just put the lid on the pot) and simmer for 20 minutes. Turn the heat off and fluff the quinoa with a fork. If there’s any liquid left in the bottom of the pot, place it back on the burner for another 3 minutes or so. Spread the cooked quinoa out on a sheet pan to cool.

Combine the room temperature quinoa in a large bowl with the oats, eggs, onion, cheese and dill. Season with salt and pepper and mix well (remember that feta cheese is salty). Shape the mixture into 6 patties with flat sides (so they fit more easily into the air fryer). Add a little water or a few more rolled oats to get the mixture to be the right consistency to make patties if necessary.

Pre-heat a sauté pan over medium heat. Add enough oil to cover the bottom of the pan. Add the quinoa burgers to the pan. Cover and let the burgers cook for 5 minutes. Check the bottom of the burger to make sure it has browned nicely. Flip the burger over, cover and cook for another 5 to 7 minutes, or until both sides are nicely browned.

While the burgers are cooking, make the cucumber dill yogurt sauce by mixing all the ingredients together.

Build your burger on the whole-wheat hamburger buns with arugula, tomato, red onion and the cucumber dill yogurt sauce.