01 -
Fill a big pot with water and lots of salt, then bring it to a boil. Cook pasta until it has a bit of bite left (al dente). Drain but save a cup of that starchy water in case you need it later.
02 -
As the water heats up, put butter and olive oil in a deep pan on medium heat. Toss in sliced onions, salt, and sugar, stirring on and off. Let them cook slowly for 25-30 minutes, so they turn soft and sweet. Go slow for the best results!
03 -
When the onions are golden and sweet, mix in the chopped garlic. Stir it around for a minute or two, just until you can smell how amazing it is. Don't let it overcook—it'll get bitter.
04 -
Pour in the optional white wine, and hear that happy sizzle! Scrape up all the tasty bits stuck to the pan. Let the wine reduce until it's almost gone but leaves a bold flavor.
05 -
Add the broth and heavy cream, stirring everything gently to mix it up. Let it simmer softly for five minutes, so it thickens slightly and picks up the golden oniony color.
06 -
Stir in the Parmesan until it's fully melted into a creamy sauce. Taste it and tweak the salt and pepper to your liking.
07 -
Throw the pasta into the sauce and give it all a good mix to coat every noodle. If things look too thick, add a bit of that reserved pasta water. Plate it up, top with parsley, and grate a bit of extra cheese over it if you’d like!