Wrap 2 stacks of 4 tortillas separately in foil. Heat in oven 10 to 15 minutes until soft and warm.
While tortillas warm, add lamb and oregano to a large skillet over medium heat; cook and stir, breaking up the lamb with a wooden spoon until browned and nearly cooked through. Drain excess fat. Stir in cumin and 1 teaspoon chipotle chile powder (use 1/2 teaspoon if you prefer milder meat), cook and stir 2 to 3 minutes more until meat is cooked through. Season to taste with kosher salt and pepper.
Meanwhile, make Chipotle Lime Crema by stirring ingredients together until smooth: Mexican crema (or sour cream), lime juice and zest, chipotle chile powder, and kosher salt. Set aside (refrigerate if making well ahead of time).
To assemble tacos: top each warm tortilla with 1/8 of lamb, desired amount of toppings, finishing with Chipotle Lime Crema, cilantro leaves and fresh or pickled jalapeño slices if desired. Serve with fresh lime wedges.
Notes
Chipotle chile powder is a smoky spice made with only smoked and dried chipotle peppers, not a standard chili powder that is a blend of spices.
Warming tortillas in the oven is easy and great for feeding several people at once, but you can also lightly fry tortillas in oil if you prefer a crunchy taco. (Tacos pictured have lightly fried tortillas.)
Note that topping amounts are 'to taste' and are not included in nutrition information.