In a large bowl, combine ground turkey, minced chipotle, adobo sauce, lime juice, lime zest, garlic, red onion, cilantro, olive oil, cumin, salt, and pepper.
Mix gently with a fork until just combined.
Divide the mixture into 4–6 patties, about 1/2 to 3/4 inch thick. Make a small indent in the center of each patty to help them cook evenly.
Preheat a grill or skillet to medium-high. Oil the grates or pan lightly to prevent sticking.
Cook the patties for 4–5 minutes per side.
During the last minute, brush the tops with BBQ sauce. If adding cheese, place a slice on each patty and cover to melt.
Use a thermometer to check for doneness: 165°F in the center. Rest the burgers for 3 minutes.
Toast the buns.
Spread a little extra BBQ sauce on the bottom bun, add the burger, and top with avocado, lettuce, tomato, and pickled red onion.