Cut roast into large chunks and salt both sides. Sear in preheated, oiled heavy bottomed pan over high heat. Flip chunks over after about 3 minutes or when the first side is becoming nicely browned. Continue to cook for another 4-5 minutes on side 2.

Transfer beef chunks and any pan fond into pressure cooker, add stock and cook on high for 90 minutes and allow pressure to release (another 30 min or so). Remove beef from cooker and transfer cooking liquid into a container - skim and discard as much fat as possible off of cooking liquid. Reserve liquid for later - there should be about 1qt/ltr left over.

Preheat large saute, add a few glugs of oil, then diced onions, poblano, minced garlic, and a pinch of salt. When veg is softened, add in cooked beef and break down slightly to shred, leaving plenty of chunks. When beef has cooked for a few minutes and has begun to take on color, add chile powder, cumin, black pepper, oregano, and the juice from a lime. Stir and allow species to bloom. Fry for about another minute or so. Season with a pinch of salt and remove from heat.

Preheat large heavy bottomed pot over medium. Add a few glugs of olive oil followed by chile powder and paprika. Stir & allow to toast until fragrant. Add ⅓ of the beef cooking liquid. Stir. Add in another third of the liquid and stir again. Once incorporated, add in most of the rest of your liquid. Save a splash in case you need to thin the sauce later. Once the liquid is incorporated & smooth, add in tomato paste, brown sugar, cider vinegar, and salt. Stir & bring to a simmer then reduce heat to med-low & cook to reduce sauce for 15-20 minutes. When ready, it should have reduced by about 30%. Remove from heat and taste for seasoning.

Grate and mix cheeses together. Wet each tortilla then heat in a skillet over medium until soft and pliable. Place warmed tortillas in a tortilla warmer (or thick container with lid to trap steam if you don't have one) until you're ready to assemble the enchiladas.

Place warmed tortillas into sauce to coat both sides then transfer to a bowl, shaking off excess sauce as you go. Spread enough roja sauce into a 9"x13"/22x33cm baking pan to lightly coat the bottom (about ¾-1c). Place 3-4oz of the meat in a line on a sauced tortilla followed by a pinch of the cheese blend. Roll tightly then place in one corner of the baking dish, seam side down. Continue filling and rolling the remaining 11 tortillas, placing each snugly against the last.

Finish by spreading 5-6 more spoonfuls of the sauce over the enchiladas and top with cheese. Bake at 375F/190C oven for about 20 minutes until cheese is well melted.

Stir to combine the sour cream, milk, lime zest, lime juice, and a pinch of salt for the lime crema.