Heat olive oil in a large skillet over medium-high heat. Add the chicken breasts and brown them for 3-5 minutes per side. Set the chicken aside.
3
In the same skillet, add the diced onion, whole garlic cloves, dried thyme, and dried rosemary. Cook until the onions are tender and the garlic starts to turn golden brown, about 5 minutes.
4
Pour in the chicken broth, and deglaze the skillet by scraping up any brown bits from the bottom using a wooden spoon.
5
Add the heavy cream and grated Parmesan cheese, stirring until the cheese has melted.
6
Return the chicken breasts to the skillet, spooning the sauce over the top.
7
Reduce the heat to low, cover the skillet, and let it simmer for 20 minutes, or until the chicken is fully cooked.