Season the pork with salt and pepper on all sides. Transfer to a medium bowl and add the adobo sauce, making sure the pork is completely coated. Let marinate, refrigerated, for 1 hour.
Put the olive oil in a medium bowl and dip in the tortilla pieces to coat each lightly. Set aside.
Oil a grill pan with some canola oil on a paper towel or cloth and heat the pan over medium-high heat.
Meanwhile, thread the skewers, alternating with 4 pieces of pork, 2 pieces of onion, 2 tortilla squares and 2 pieces of pineapple. Grill until the pork is cooked through and the skewer components are lightly charred on all sides, about 5 minutes per side. Serve immediately with lime wedges and Cilantro Crema.
Combine the cilantro, Mexican crema, lime juice, avocado and jalapeno in a blender and process until smooth. Add 1 tablespoon water and blend for 10 seconds. Adjust the seasoning to taste with salt and freshly ground black pepper.