In a large mixing bowl, combine the turkey mince, fresh breadcrumbs, egg yolk, grated cheddar cheese, finely chopped jalapeño, chives, garlic powder, oregano, salt, and black pepper. Use your hands or a fork to mix until just blended, being careful not to overmix.

Wet your hands slightly to prevent sticking, then divide the turkey mixture into four equal portions. Shape each portion into a uniform patty, about ¾-inch thick, making a slight indentation in the center of each patty.

Preheat your grill to medium-high heat, around 375°F to 400°F (190°C to 200°C). Lightly oil the grill grates to prevent sticking.

Place the formed patties on the hot grill and grill for 5 to 7 minutes per side until a golden brown crust forms and they reach an internal temperature of 165°F (74°C).

As the last side of the patties finishes cooking, add the burger buns cut side down on the grill. Toast them for about 1 to 2 minutes until they’re lightly golden.

Spread mayonnaise on the bottom half of each bun, then layer with crisp lettuce, the grilled turkey patty, a slice of cheese, refreshing tomato slices, and some onion rings. Top with the other half of the bun.

Serve immediately while hot and juicy, paired with sides like sweet potato fries or a fresh salad.