In a small pan, toast the fennel and black pepper.
Add the fennel, black pepper, paprika, and salt to a spice grinder and grind.
Put the pork in a large, (2-gallon, if possible), resealable plastic bag. Add the garlic, vinegar, olive oil and the spices. Seal the bag, and massage the marinade all over the pork. Put the bag into a glass or metal pan (in case bag leaks) and refrigerate for 4 hours. Remove from refrigerator and let come to room temperature.
Add 2 tablespoons cilantro, lime juice and 1 cup of crema to a small bowl. Combine well, pour into squeeze bottle and refrigerate.
Preheat the oven to 375 degrees F.
Heat corn tortillas in oven, wrapped in foil in packs of 8, in the oven while you are grilling the pork.
Heat an indoor or outdoor grill to medium heat. Add the pork steaks and grill until medium, turning, for approximately 10 minutes total. Remove to a cutting board and let rest 5 minutes, then slice into long thin strips.
Serve in warmed tortillas, topped with tapenade, squeezed with lime wedges, drizzled with crema and topped with remaining chopped fresh cilantro.