You can use Chipotle en Adobo paste instead of chilli paste (available at Waitrose and Ocado in the UK).
While the lamb is delicious served as tacos, it is also lovely over rice or in a salad.
For a lighter version
Skim any fat from the sauce – put in the fridge and discard the fat which will solidify on the surface of the sauce.
For those following Slimming world (as I am currently) serve your lamb al pastor on crunchy lettuce leaves instead of tortillas and replace the avocado witch chopped tomatoes.
Nutritional information is always approximate, and will depend on ingredients you choose.