01 - In a large mixing bowl, gently fold together ground chicken, finely chopped spinach, shredded white cheddar, breadcrumbs or almond flour, egg, minced garlic, Dijon mustard, onion powder, salt, and black pepper until evenly incorporated. Do not overmix.
02 - Divide the mixture evenly into 4 portions. With dampened hands, shape each portion into a patty approximately 1/2 inch thick.
03 - Heat olive oil in a large skillet over medium heat. Add the patties and sear for 4 to 5 minutes per side, until golden brown and the internal temperature reaches 165°F. Alternatively, grill patties over medium heat for the same duration.
04 - Toast buns if desired. Arrange each cooked patty on the bottom bun and top with preferred garnishes such as sliced white cheddar, avocado, tomato, red onion, and greens.
05 - Serve burgers hot with your choice of side, such as sweet potato fries, fresh salad, or roasted vegetables.