Preheat the broiler. Stem and seed the chile peppers and soak in warm water until soft, about 15 minutes. Drain.
Heat the olive oil in a saucepan over medium heat. Add the onions and garlic and cook, stirring occasionally, until the onions are translucent, about 5 minutes. Transfer the mixture to a blender and add the chiles, chicken broth, peanut butter, sugar and oregano. Coarsely crumble 1/4 cup tortilla chips, add to the blender and puree until smooth. Return the mixture to the saucepan and simmer, stirring, about 5 minutes. Stir in the chocolate until melted. Season the mole with salt and pepper.
Place the remaining tortilla chips in a baking dish. Pour about 2 cups mole on top (reserve the rest for dipping); sprinkle with the cheese. Broil until the cheese melts, about 2 minutes. Top with the crema and cilantro.
Photograph by Yunhee Kim
Recipe courtesy Marcela Valladolid for Food Network Magazine