Bring a large pot of water to a boil. Add a little salt and angel hair pasta. Cook pasta according to package directions, until al dente. Drain pasta.
While pasta is cooking, melt butter in a large skillet over medium heat. Add pancetta and cook for about 3 minutes. Add jalapeño pepper and cook for another 3 minutes, until pancetta is browned. Add garlic and cook for just one more minute.
Add cream to skillet and let it come to a simmer. Simmer for about 5 minutes to thicken sauce, stirring occasionally. Stir in cheese, pepper, and salt until combined. Add pasta to skillet and stir to coat pasta in sauce (it helps if you use tongs).
Serve on plates and top with additional parmesan cheese and parsley.