Preheat oven to 400°F (200°C).
In a large oven-safe skillet, toss halved baby potatoes with 1 tablespoon olive oil, salt, and pepper.
Roast potatoes in the oven for 15 minutes or until they begin to soften.
Move potatoes to the edges of the skillet and place chicken thighs in the center. Season chicken with salt, pepper, and thyme.
Return skillet to the stovetop over medium-high heat and sear chicken for 5 minutes per side until golden brown.
Add sliced mushrooms and minced garlic to the skillet, sautéing for 3-4 minutes until mushrooms are tender.
Pour in chicken broth and heavy cream, scraping the bottom of the pan to deglaze.
Simmer for 5-7 minutes until the sauce thickens and chicken reaches an internal temperature of 165°F (74°C).
Stir in Parmesan cheese until melted and garnish with fresh parsley before serving.