Try "Cielo Tinto" on Av. Carranza street #700
And some other local food u can try:
-Enchiladas Potosinas: the most famous local food in San Luis made of tortilla, mexican cheese and Mole (a sauce made of different ingredients) really good one!
-Cabuches: an appetizer cooked with flowers
-Asado de Boda: pork with chile ancho (some type of mexican chilli)
-Zacahuil: special tamal
-Migadas about 5 years ago