Place a medium saucepot over medium-high heat with the beef stock and ancho chilies. Bring the liquid to a bubble then reduce heat to medium and simmer for 15 minutes until chilies have softened. Transfer mixture to a blender or food processor and -- very carefully, this mixture is very hot! -- puree it until smooth. Reserve.
While the chilies are simmering, place a large, heavy-bottomed pot over medium-high heat with 2 turns of the pan of EVOO, about 2 tablespoons. Add the sirloin and cook until golden brown, 6-7 minutes. Add the onion, garlic, raisins and spices to the pan, season with salt and pepper, and cook until the veggies are tender, 5-6 minutes. Add the tomato paste to the pan and cook until deep golden brown and aromatic, about 1 minute.