Heat a heavy based casserole pan to medium heat and add the duck legs skin side down, no oil required but seasoned with salt. Cook for 10 minutes until the fat starts to render. Turnover and cook for a further 2-3 minutes. Remove the legs from the pan and drain most of the excess fat.
Add half of the onion, the garlic and spices and cook for a minute until fragrant, then mix in tomato paste along with coriander roots and stems, vinegar and stock (or enough to almost submerge duck). Return the duck and cook, uncovered in the oven for 1 1/2-2 hours or until duck meat falls off the bone. Once cooked remove meat from bones to make pulled duck and discard bones. Allow the sauce to bubble away to reduce by a further third. Fold 3 tablespoons of the sauce through the duck.
For the salsa, add pineapple, jalapeno chilli, lime zest and juice and a pinch of salt in a bowl and stir to combine.
Warm tortillas up in a pan over a medium heat. Add the saucy meat to the middle of each tortilla and top with the salsa. Serve and enjoy!
