Rinse pork and pat dry with a paper towel. Cut into large chunks. Salt and pepper the pork.
In a 6-quart stock pot over medium-high heat, add 1 tbsp olive oil. When hot, add pork pieces and brown on all sides, about 3 minutes per side.
Add the cumin, oregano, garlic cloves, orange juice, water and bay leaves to the pot.
Cover and simmer over low heat for 3-4 hours, turning the meat at least once during cooking, until the meat is tender (it falls apart when forked). Alternative: If cooking in a slow cooker, cover and cook on low heat 5-6 hours. In the pressure cooker, cook for 45 minutes on high pressure.
Remove pork from the braising liquid.
For the tacos
Heat ½ tbsp olive oil in a skillet over high heat. Add the shredded meat to the pan. Allow it to brown for at least 1 minute untouched. Flip the meat over and brown an additional 1 minute. Remove from heat.
Warm the keto tortillas.
Place an ample amount of carnitas in the center of each tortilla.
Sprinkle each taco with onions, cilantro, lime juice and jalapeno slices, to taste.