In a medium bowl, combine the ground chicken with diced red onion, minced garlic, finely chopped sun-dried tomatoes, roughly chopped baby spinach, fresh dill, dried oregano, kosher salt, and ground black pepper. Mix thoroughly until well blended.

Divide the mixture into four equal portions and shape each into a large, round patty about ¾-inch thick, making an indentation in the center.

Heat a large skillet over medium heat, add a drizzle of olive oil, and carefully place the patties in the skillet. Cook for approximately 5 minutes on each side until golden brown and internal temperature reaches 165°F.

Remove the patties from the skillet and let them rest for a couple of minutes. Serve on soft hamburger buns, wrapped in lettuce, or as is, with your favorite toppings.