01 - Bring a large pot of generously salted water to a rolling boil. Add the wide egg noodles and cook according to package directions until al dente. Drain through a colander and set aside.
02 - While the noodles cook, melt the butter in a large skillet over medium heat. Add the finely chopped onion and sauté until soft and translucent, about 3 to 4 minutes. Add the minced garlic and cook for an additional 30 seconds until fragrant.
03 - Sprinkle the all-purpose flour over the onion and garlic mixture. Stir constantly for 1 minute to form a smooth roux and cook off the raw flour taste.
04 - Gradually whisk in the whole milk and broth, stirring until completely smooth with no lumps remaining. Bring the mixture to a gentle simmer and cook for 3 to 4 minutes, or until the sauce has slightly thickened.
05 - Stir in the heavy cream, salt, black pepper, and garlic powder. Continue cooking for 2 more minutes, then add the grated Parmesan cheese. Stir until the cheese has fully melted and the sauce is creamy and smooth.
06 - Add the drained egg noodles to the skillet, tossing gently to coat them evenly in the creamy sauce. Taste and adjust the seasoning with additional salt or pepper as needed.
07 - Transfer to serving bowls immediately. Garnish with chopped fresh parsley and an extra sprinkle of Parmesan cheese if desired.