Season chicken breasts with salt, pepper, and dried Italian seasoning on both sides.
Heat olive oil in a large skillet over medium-high heat. Sear chicken until golden brown, approximately 6 minutes per side. Remove chicken from skillet and set aside.
In the same skillet, melt butter over medium heat. Add halved potatoes and cook, covered, for 10-12 minutes or until tender and golden brown.
Incorporate sliced mushrooms into the skillet with the potatoes. Sauté for 5 minutes until mushrooms have released their moisture and browned.
Add minced garlic and cook for 60 seconds until fragrant.
Pour in chicken broth to deglaze the pan, scraping the bottom to release fond. Stir in heavy cream and bring to a light simmer.
Reduce heat to low and whisk in grated Parmesan cheese until the sauce thickens slightly.
Fold in fresh baby spinach and stir until just wilted.
Return chicken breasts to the skillet. Spoon the cream sauce over the chicken and simmer for 5 minutes until the internal temperature of the chicken reaches 165°F (74°C).