Place the ground turkey into a large mixing bowl, then add the egg, oat flour, minced garlic, finely chopped onion, salt, and black pepper. Using clean hands or a fork, gently mix everything together just until the ingredients are evenly combined. Stop as soon as the mixture comes together—overmixing can make the meatballs dense and tough instead of tender and juicy.
Scoop small portions of the mixture and roll them between your palms to form evenly sized meatballs, about the size of a golf ball. Keeping them uniform helps ensure they cook evenly. Place the shaped meatballs on a plate or tray while you prepare the skillet.
Heat the olive oil in a large skillet over medium heat. Once the oil is hot, carefully add the meatballs in a single layer, leaving space between them. Let them cook undisturbed for a few minutes to develop a golden-brown crust, then turn gently and continue cooking until all sides are browned. At this stage, they should be mostly cooked but not fully done. Transfer the meatballs to a plate and set aside.
Using the same skillet, add the sliced mushrooms directly to the pan. Cook over medium heat, stirring occasionally, until the mushrooms release their moisture and begin to soften and brown. This step builds deep, savory flavor and forms the base of the sauce.
Sprinkle in the paprika and stir to coat the mushrooms evenly. Pour in the chicken broth and use a spoon or spatula to scrape the bottom of the pan, releasing any browned bits left behind from cooking the meatballs. These bits add richness and depth to the sauce. Let the mixture simmer gently for a few minutes.
Lower the heat and slowly stir in the Greek yogurt, mixing gently until the sauce becomes smooth and creamy. Keeping the heat low is important to prevent the yogurt from curdling. Once the sauce is cohesive, return the meatballs to the skillet and spoon the sauce over them.
Let everything simmer gently for several minutes, just until the meatballs are fully cooked through and the sauce thickens to a creamy, velvety consistency. The finished dish should feel rich and comforting while still light and protein-packed, ready to serve or portion for meal prep.