Heat a pot of salted water to boil, and cook the pasta according to package instructions. Cook to al dente.
Next, start steaming the asparagus. Start by putting 1/3 cup of water into a saucepan and heat it over high heat. Once the pan gets hot, reduce the heat to medium. Throw in the chopped asparagus, cover with a lid, and steam for 3-5 minutes or until fork tender. You can also use a rice cooker or a vegetable steaming basket to cook the asparagus.
Next, cook the ground sausage by heating the pot you will eventually make the pasta in on high. Put in the whole pound of sausage and break it up with a spatula as it begins to cook and brown. No need to add oil to this step. The fat in the sausage will prevent the meat from sticking to the pan and burning.
Once it’s done, drain the meat and set aside. Use the residual sausage oil and crumbs left in the pan to start cooking your pasta sauce. This will give it extra flavor!
Then heat the same pot with the olive oil and butter.
Until the butter is fully melted in the pan, throw in the onions. Season with salt and pepper. Caramelize for 5-10 minutes.
Add in the minced garlic, and sauté until fragrant, about 2 minutes. Then add in the nutmeg and sauté for another minute.
Add the 2 cups of half and half and let it simmer for roughly 10 minutes, until the sauce starts to thicken slightly.
Take the small bowl of whipped egg yolks, and slowly drizzle it into the pot as you quickly whisk the cream mixture. You don’t want to dump all the egg yolk into the sauce at once, because then it will clump and cook, and prevent your sauce from becoming extra creamy.
Once you’ve added the egg yolk and whisked the sauce for roughly a minute, add the Romano and parmesan cheese next. You’ll want to slowly add the cheese into the sauce as you did with the egg yolk.
Add back in your spaghetti, sausage and asparagus until the sauce fully coats the noodles, sausage and asparagus.
Garnish with chopped Italian parsley and extra grated cheese. Serve and enjoy!