Cook pasta according to the directions on the package. Reserve some pasta water and drain the rest. Set pasta aside.
In same pot or a large frying pan, melt butter over medium heat. Cook onion and garlic until softened and fragrant, about 4-6 minutes.
Add broth and Boursin, stir until melted.
Stir in fresh herbs and pasta. Thin with pasta water if needed.
Garnish and serve immediately.
Notes
Reserve a bit of the salted pasta water! This will help thin out the sauce if needed.
Use fresh herbs instead of dried. Herbs are one of the most prominent ingredients in this dish, so using fresh will give it a much better flavor and texture.