Add the turkey, almond flour, yogurt, mustard, egg, salt, black pepper, garlic and onion to your food processor's bowl. Process until finely chopped and incorporated, stopping once to scrape the sides of the food processor bowl with a spatula.
Transfer the mixture to a large bowl. Fold in the parsley. (If you add the parsley to the food processor, the patties will be tinted green - still delicious, but not pretty to look at. Speaking from experience).
The mixture should be smooth and easy to work with. If it's very dry and crumbly, add a little more yogurt. If it's very wet, add a little more almond flour.
Heat a double-burner griddle over medium heat, about 4 minutes. Brush with olive oil. Use a 1/4-cup ice cream scoop or measuring cup to measure out the patties, placing them on the griddle and flattening with a spatula. Cook about 3 minutes on each side, until well-browned.