Slice the pork loin thinly, diagonally across the loin. We’re talking 3–5mm slices.
The dried chilis need to be rehydrated in water: pour hot water over the chilis, but take them off the heat immediately. Snip the chilis with a pair of scissors to allow water into the chili and to allow the whole chilis to be covered in water.
Remove the membranes and seeds from the chilis and slice the chilis.
After step 3, gentlemen in particular, wash your hands thoroughly. Don’t make me explain.
Throw all the ingredients into a blender, but not the pork, obviously.
When the above ingredients have formed a nice smooth-ish marinade, place the pork slices in a large plastic freezer bag and pour the paste over. Combine thoroughly.
Marinate in the refrigerator for at least 8hrs, but 24hrs is more desirable.
Pre-heat the oven to a moderate temperature, say 350˚F or about 185˚C. Take the pieces of pork out of the freezer bag and form into a ‘roll’ shape on a piece of aluminum foil; add plenty of the marinade before folding over and making the ‘round’ shape.
Place the pork in the oven and prepare for some beautiful aromas. It should take around an hour to cook. The temperature (which should be measured with a meat thermometer) should be around 160˚F or 72˚C.
For those paranoid about ‘pink’ meat, don’t despair, you can finish the pork in a grill pan to your heart’s content – which is what we’re about to do.
Put a grill pan on the stovetop at a medium-high heat. Add some cooking oil (no, not olive oil), and add some pieces of the pork, and cook to your liking. To achieve the kind of texture that you get from the vertical spit, you need some pieces to have a little crunch.
Place some corn tortillas in a pan to heat through.
Place a small amount of pork on each tortilla, add a sprinkle each of cilantro, onions and pineapple (if desired), and get everyone to add their own preferred salsa.
Have a michelada or a good stiff shot of tequila and a cold beer on the side. You could also serve with a margarita, but remember this is street food we’re celebrating!