How to Make It
Pour 1/4 inch of water into a pressure cooker and add the pork. Cover and cook at 15 PSI (see Note) for 25 minutes, regulating the heat to prevent excessive steam from escaping through the valve. Turn off the heat and wait for the pressure cooker to depressurize so that the lid can be removed without force, about 10 minutes. Using a slotted spoon, transfer the meat to a strainer. Stir the achiote paste and both chile powders into the pan juices and season with salt.
In a medium skillet, heat 1/2 inch of oil until shimmering. Working in batches, fry the pork over high heat, turning once, until crispy, 3 minutes. Season with salt. Add the meat to the sauce and stir to coat. Serve the carnitas with tortillas, cilantro and lime wedges.
Achiote paste is available at specialty food shops and online at mexgrocer.com.
Fifteen pounds per square inch (PSI) is the most common setting for pressure cookers. Products vary, however, so be sure to consult the owner's manual.