To roast the garlic:
Separate, but do not peel the cloves from 2 to 3 heads of garlic. Lightly brush the cloves with vegetable oil and roast for 10 to 15 minutes at 350°F. When cool, pinch the cloves. The meat will slip right out. Preheat the oven to 375°F.

To prepare the sausage crust:
Combine all of the ingredients in a medium bowl. Heat 2 tablespoons of the peanut oil in a large ovenproof skillet over medium-high heat. Season the pork tenderloins with salt and pepper. When the oil is almost smoking, place the tenderloins into the skillet. Do not crowd; if your pan isn't large enough, cook in two batches. Cook until browned all over, about 8 minutes. Transfer to a large plate. Set aside to cool.

Wipe the skillet, add the remaining 2 tablespoons oil, and place it over medium heat. Pat the crust mixture evenly on the tenderloins. Place them in the skillet and sear, turning to brown all over, 5 to 7 minutes. Transfer the skillet into the oven and cook another 10 minutes, or until the internal temperature is 145°F. Let the meat rest before slicing into thick slices. The meat will continue to cook as it rests.

To make the ancho chile sauce:
Remove the stems from the chiles and add to a large pot with the onion, garlic, and chicken stock. Bring to a boil, then reduce the heat, and simmer for 15 minutes. Remove the garlic, onion and chiles from the liquid; reserve solids and liquid. Transfer the garlic, onion, and chiles to a food processor or blender and puree. Add about 2 cups of the reserved liquid and process again. Add additional stock, if necessary, to create a thick sauce.

To make the beet mashed potatoes:
Boil the potatoes and beets in a large pot of boiling water until tender, 20 to 30 minutes. Remove from the pot, drain, and let cool. Remove the skins from the potatoes and beets, and transfer to a mixing bowl. With a mixer, beat the potatoes and beets with the roasted garlic and butter until well mashed. Add salt and pepper to taste.