Preheat your cooking surface. Heat a grill, grill pan, or skillet to medium-high. Oil the grates or pan lightly to prevent sticking.
Mix the patties. In a bowl, combine ground turkey, breadcrumbs, egg, grated onion (or onion powder), garlic powder, smoked paprika, salt, and pepper.
Stir gently until just combined—don’t overwork it.
Form the burgers. Divide into 4–6 patties about 1/2 inch thick. Make a small indentation in the center of each to prevent doming.
Grill the pineapple. Brush pineapple rings with a little olive oil. Grill 2–3 minutes per side until lightly charred and caramelized.
Set aside.
Cook the patties. Brush patties with oil. Cook 4–5 minutes per side, depending on thickness. During the last minute, brush each patty with BBQ sauce.
If adding cheese, place it on top to melt.
Check doneness. Turkey should reach an internal temperature of 165°F (74°C). Remove and rest for 3–4 minutes.
Toast the buns. Place buns cut-side down on the grill or pan for 30–60 seconds until golden.
Assemble. Spread BBQ sauce on buns. Layer lettuce or tomato (optional), the turkey patty, a grilled pineapple ring, and red onion or jalapeños if you like.
Top with the bun and serve.