In a large frying pan, cook the pancetta over medium-low heat, stirring occasionally, for about 15 minutes until crisp. Remove with a slotted spoon, drain on paper towels, and set aside; leave 1 tbsp of fat in the pan.
Add the butter, then the garlic, shallots and sugar, with a little salt and pepper. Cover, reduce to very low heat, and cook for about 15 minutes until the shallots are soft and translucent, then uncover, raise the heat to medium-high, and cook, stirring constantly, for about 10 minutes until deep golden brown; don't let them burn.
Add the stock and simmer for about 7 minutes until reduced by a third, scraping up the browned bits from the bottom.
Bring a large pot of salted water to a boil for the pasta. Roughly chop most of the herbs, setting a small handful aside.
Cook the pasta, drain, and return it to the pot. Add the cream to the sauce and simmer for 2 minutes until slightly thickened, then stir in the chopped herbs.
Add the pasta to the sauce and toss together over low heat for 1 minute. Fry the reserved herbs in ½ tsp olive oil until crisp for garnish. Stir in the pancetta and half the Parmesan.
Divide among plates, garnish with the fried herbs, and serve the remaining Parmesan on the side.