Heat the oven to 425°F.
Heat the butter and oil over medium heat in a deep skillet or pot. When hot, add the onion, carrot, celery, garlic, and half of the parsley. Cook, stirring, until the vegetables are soft, but not brown. Add the meat to the pot and cook, breaking up and browning. Add the wine and cook it down until it is mostly evaporated.
Stir in the crushed tomatoes, tomato paste, milk, and bay leaf. Simmer until slightly thickened, about 20 minutes.
Give the sauce a stir, then add ½ tablespoon of fish sauce and taste, adjusting with salt and pepper as needed.
In another oven safe skillet, heat up the butter over medium heat. Add the gnocchi and pan fry, turning as needed, until golden, about 3-4 minutes. The gnocchi will continue to cook in the sauce as it bakes in the oven. Add the bolognese sauce to the skillet (you might have a bit extra) and stir to combine. Top with the shredded mozzarella and shaved parmesan, if using.
Bake for 20-30 minutes, or until cheese is melted and sauce is bubbly. Enjoy!
