To make the birria: Season the meat with salt and pepper, then place in a large baking dish. Clean and devein the peppers. Slightly toast them in a skillet over a medium heat, making sure you do not burn them as burning the peppers will make the dish taste bitter. After, soak them in hot water, covering them for 20 minutes.
Roast the tomatoes, onion, and garlic by cooking over medium heat for approximately 8 to 10 minutes, and place in your blender.
Toast the whole clove, cumin seeds, and black peppercorns (this is a quick step that only takes a few seconds). Place them in your blender along with the herbs, cinnamon, ginger, achiote, and the vinegar. Once peppers are soft, drain, add to the blender, and puree until you have a smooth sauce. Add a few tablespoons of water only if your blender is having a hard time processing it. Season the sauce with salt.
Pour the sauce over the meat, making sure it is covered all over with the salsa. Cover the baking dish with aluminum foil and refrigerate overnight, or for at least 4 hours, to allow all the meat to absorb the flavors. Preheat the oven to 350°F. Bake the meat for about 4 hours, or until it is fork tender.
To make the crispy epazote: Heat vegetable oil in a fryer or pot. Once hot, add epazote leaves and fry for approximately 1 to 2 minutes, until crisp. Remove from heat and salt to taste.
To make the hibiscus pickled onions: Place the thinly sliced red onion in a large bowl. Place all other ingredients, plus 4 cups water, in a sauce pot and bring to a low boil. As soon as low boil begins, turn off the heat. Strain hot liquid over onions and let steep until cool (approximately 1 hour), then place in a large jar or container. Store in in refrigerator for 2 to 4 hours or overnight (the longer the better).
To make the quesotacos: Dip each tortilla in hot braising jus and place on griddle or nonstick pan. Place approximately 1 ounce of shredded Oaxaca cheese and 2 ounces of shredded short rib birria onto the tortilla, then fold it over like you are making a quesadilla. Cook on both sides until a crispy texture starts to form. Place each quesataco on a plate and garnish with cilantro, red onion, a squeeze of lime wedge, crispy epazote, hibiscus pickled onions and a drizzle of crema Mexicana agria.