Peel pears and remove the core from the bottom using a melon baller, keeping the stem end intact. Scrub the pears with a new abrasive plastic scrubbing pad to remove any rough edges or textures left from the knife. Set the pears aside.
In a large stockpot, combine the tardio, red wine, sugar, cinnamon sticks, star anise, and cloves and bring to a boil. Add the pears and cook until tender, about 25 minutes. Remove the pears and reduce the remaining liquid by half, about 45 minutes.
In a food processor, puree the cabrales and toasted walnuts, and set aside. Place the mixture in a pastry bag and stuff the pears with walnut and cabrales mixture.