Remove them from the pot and set aside for later then add the onion and cook until it becomes translucent.
½ cup diced white onion
Add the garlic and rosemary and cook just until they become fragrant.
2 cloves garlic, 2 teaspoons fresh rosemary
Add the ground beef, ½ teaspoon of the salt, sage and red pepper to the pot.
1 pound 80/20 ground beef, 1 teaspoon dried rubbed sage, 1 teaspoon crushed red pepper, ½ teaspoon . kosher salt
Crumble the beef as it cooks until it turns a dark brown color then remove it from the pot and wipe out any excess grease and beef bits.
Pour in the chicken broth and add the remaining salt and bring it to a boil then add the pasta and let it cook for the amount of time that the box instructions indicate.
4 ½ cups low sodium chicken broth, 10 ounces pasta shells, 1 teaspoon . kosher salt
Remove the pot from the heat and stir in the heavy cream.
¼ cup heavy cream
Then add the mozzarella, white cheddar, gouda and cream cheese and stir until melted.
1 cup mozzarella cheese, 1 cup white cheddar cheese, ½ cup smoked gouda cheese, 4 ounces cream cheese
Stir in the cooked mushrooms and beef then serve with freshly minced parsley.
Notes
This pasta can be stored in an airtight container in the fridge for up to 3 days.