Cut the short ribs between the bones and remove excess fat.
Dry roast the ancho chiles on a comal, over an open fire or in a cast-iron pan over medium-high heat until beginning to blacken and blister. Transfer to a spice grinder and process to a fine powder.
In the same manner, dry roast the onions and garlic until beginning to blacken and blister. Combine the piloncillo, pulque, agave, tequila and ancho powder in a blender; blend until smooth.
Heat the lard in a skillet and fry the chile mixture. Season with salt and let cool. Marinate the short ribs overnight in the chile mixture.
The next day, preheat the oven to 375 degrees F. Dry roast the agave leaves over medium-high heat. Arrange the leaves in the bottom of a pan, to act as a steamer. Place the short ribs on top and cover with the marinade. Cover with the cactus paddles and seal with foil or a tight-fitting lid. Transfer to the oven and cook for about 4 hours.
Slice the cactus paddles into strips and divide the cactus and short ribs among 4 serving dishes. Serve with beans and tortillas.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.