1In a large skillet over medium-high heat, toast the chiles, turning occasionally, until blistered and fragrant, 4 to 5 minutes. Transfer the chiles to a bowl of hot water, cover and set aside for 15 minutes.
2Remove the chiles from the water and stem and seed them. Place the chiles, onion, vinegar, and garlic in the bowl of a food processor or the jar of a blender and process to purée, scraping down the bowl or jar as needed.
3Transfer the chile mixture to a large bowl and add the pork, paprika, oregano, salt, coriander, cumin, pepper, and cinnamon, mixing until well combined. Cover and refrigerate overnight.
4In a large skillet over medium heat, cook the pork mixture, breaking it up with a spoon or spatula, until no longer pink, 5 to 6 minutes. Set aside to cool slightly.
5Meanwhile, in the bowl of a food processor, combine avocado, cilantro, sour cream, lime juice, and olive oil and process to purée, scraping down the bowl as necessary. Add salt to taste and set aside in the refrigerator.
6Stir the cheese into the pork mixture. Arrange a 5- or 6-inch round of empanada dough or an empanada shell on a lightly floured work surface. Spoon 1 1/2 to 2 tablespoons of pork mixture on top, moisten the edges of the shell with water, and fold the shell over the filling, pressing it with a fork to seal. Repeat with the remaining shells and pork mixture, flouring the work surface as necessary.
7Preheat the oven to 200 degrees F. Arrange two or three paper towel-lined baking sheets in the oven.
8Pour canola oil into a large, heavy saucepan or small stockpot to 1-inch deep and warm it to 350 degrees F. over medium heat. Cook the empanadas in batches, turning occasionally and adjusting the heat to main 350 degrees F., until golden, 3 to 4 minutes. Transfer to the prepared baking sheets to keep warm.
9Serve the empanadas with the avocado crema on the side.