Prepare a smoker for cold smoke. Place duck breasts on a smoker rack and put in the smoker for 15 minutes. Remove from the smoker.
In a small bowl add fresh lime juice to sour cream and stir. Season with salt, to taste, and refrigerate until ready to serve.
Preheat oven to 350 degrees F. Place the duck breasts in an ovenproof saute pan and place in the oven. Roast duck for 10 minutes or until medium rare. Remove from the oven and allow to cool.
Using a sharp knife, dice the duck breast into 1/2-inch pieces. Place the canola oil in a large saute pan over medium high heat. Add diced duck and season with salt and pepper. Stir in the barbeque sauce and bring to a boil and immediately remove from heat.
Place 4 flour tortillas on a clean cutting board. Divide the duck mixture onto the tortillas. Sprinkle the sauteed Maui onion, mango, poblano chili, red onion, cheese, and cilantro evenly over duck mixture. Top with the remaining 4 tortillas and brush each side with canola oil. Bring a large saute pan or griddle to medium heat.
Place 1 tortilla stack in the pan or griddle and cook until golden brown or about 3 minutes. Using a spatula flip tortilla over to cook other side. Remove from pan and place on cutting board and cut into 6 wedges. Place on a warm plate and dab lime sour cream on each wedge and garnish with a cilantro sprig. Repeat with the remaining tortilla stacks.