01 - Combine ground turkey or chicken, egg, oats, red onion, Dijon mustard, garlic, parsley, smoked paprika, salt, and black pepper in a large bowl. Mix gently until just combined—avoid overworking the meat to maintain tenderness.
02 - Divide mixture into 4 equal portions and form each into a patty approximately 1/2 inch thick. Press gently to create uniform thickness for even cooking.
03 - Heat a nonstick skillet or grill over medium-high heat. Lightly oil the surface if necessary to prevent sticking.
04 - Place patties on the preheated surface and cook for 4-5 minutes per side. Cook until golden brown and fully cooked through, reaching an internal temperature of 165°F.
05 - Lightly toast whole wheat buns on the skillet or grill for 1-2 minutes until golden and crisp, if desired.
06 - Place a lettuce leaf on the bottom bun, top with a cooked patty, add Greek yogurt spread, layer with tomato slices, red onion, and avocado if using. Finish with the top bun and serve immediately.