Special Equipment: parchment paper
Preheat oven to 375 degrees F.
Brown chorizo in a skillet over medium-high heat, about 8 to 10 minutes. Drain and place into a large mixing bowl. Add the cheese, red onion, egg, cream cheese, sour cream, hot sauce, and salt and pepper, to taste. Press into jalapeno halves and assemble on a parchment lined baking sheet. Bake until golden and bubbly, about 20 minutes.