1. Preheat the oven to 375 degrees F. Slice off the top 1 1/2 inches of the pumpkin and discard. Scoop out the seeds and stringy pulp.
2. Heat the chorizo in a medium pot over medium-high heat until the fat begins to render, about 5 minutes. Add the jalapeno, green chiles, cumin and cayenne and cook, stirring, until the jalapeno softens, about 2 minutes. Stir in the flour and cook, stirring, until the flour is slightly toasted, about 2 minutes. Add the chicken broth and bring to a boil. Reduce the heat to medium and stir in the cheeses. Cook, stirring occasionally, until the cheese melts and the mixture is creamy, about 3 more minutes. Place the pumpkin in a small baking dish and fill the pumpkin with the cheese mixture. Add 1 inch of boiling water to the baking dish. Cover loosely with foil and bake until the pumpkin is tender, about 1 hour, 20 minutes. Remove the foil and continue baking until the cheese is golden and bubbly, 20 to 25 more minutes. Let cool 5 to 10 minutes. Sprinkle with cilantro and serve with tortilla chips.