How to Make It
In a large bowl, mix the tamarind concentrate with the honey, sherry vinegar and 1/4 cup of the oil. Add the pork, season with salt and pepper and stir to coat. Let marinate at room temperature for 1 hour. Drain the pork and pat dry.
Preheat the oven to 375°. In a large enameled cast-iron casserole, heat 2 tablespoons of the oil. Add half of the pork and cook over moderately high heat, turning occasionally, until browned all over, about 6 minutes. Transfer the pork to an 8-by-11-inch baking dish. Repeat with 2 more tablespoons of oil and the remaining meat. Add two-thirds of the chopped white onion and 2 cups of oil to the baking dish. Cover with foil and bake for about 2 hours, or until the meat is very tender.
Meanwhile, wrap the garlic cloves in foil and bake for 1 hour, or until softened. Let cool slightly, then peel the cloves. In a small bowl, mash the avocado with the garlic. Stir in 1 tablespoon of the lime juice and season with salt and pepper.
Using a sharp knife, peel the oranges, removing all the bitter white pith. Working over a bowl, cut in between the membranes to release the segments. Squeeze the orange membranes to extract the juice. Stir in the red onion, cilantro and habanero and the 2 remaining tablespoons of fresh lime juice.
In a medium bowl, combine the Requeson cheese with the tomato, jalapeño and the remaining one-third of the chopped white onion. Season the Requeson with salt and pepper.
Brush the tortillas lightly with oil, then stack and wrap them in foil. Heat the tortillas in the oven until warm. Drain the pork on paper towels. Serve the carnitas, encouraging guests to fill the tortillas with the Requeson, meat and guacamole. Serve the orange salsa on the side.
Tamarind concentrate is used in Latin and South Asian dishes to add a slightly sweet and sour flavor. It is available at most Latin and Indian markets.
The habaneros that add spice to this recipe are short, squat, orange chiles that are lightly fruity in flavor and extremely hot—at least two times hotter than jalapeños. If you prefer less heat, you can substitute a milder chile or serve your favorite hot sauce on the side.