01 - In a large bowl, combine ground turkey, finely chopped onion, minced garlic, chopped parsley, Dijon mustard, smoked paprika, black pepper, and salt. Mix gently until just incorporated.
02 - Divide the turkey mixture into four equal portions and shape each into a burger patty.
03 - Heat olive oil in a grill pan or skillet over medium heat. Cook each patty for 5 to 6 minutes per side until the internal temperature reaches 165°F.
04 - While cooking, toss avocado slices with lemon juice, salt, and pepper to prevent browning.
05 - Lightly toast burger buns if desired.
06 - Spread mayonnaise, if using, on the bottom bun. Layer with lettuce, turkey patty, tomato slices, red onion, and avocado. Finish with the top bun.
07 - Serve immediately with preferred side dishes.