Toss the three cheeses with the cornflour and set aside.
Fry the bacon in a non-stick saute pan until quite crisp. Add jalapenos and garlic and fry until fragrant. Add cream, cream cheese, salt, pepper and chicken. Stir to combine and simmer briefly. Turn the heat off and stir through half the cheese mix. Add the cooked pasta and the cup of pasta water. Mix well, then remove from heat and transfer to baking dish. Top with remaining cheese mix. Bake for 15 minutes at 180°C, then grill on high until the top is a pleasing, crisp brown.