Pat the chicken breasts dry and season both sides with salt, pepper, and the Italian seasoning. This helps build flavor and sear nicely without needing a lot of effort.
Heat the olive oil in a large skillet over medium-high heat. Sear the chicken for about 4-5 minutes per side, until golden brown and cooked through. Remove the chicken from the pan and set aside to rest.
In the same skillet, lower the heat to medium. Add the minced garlic and sauté for about 30 seconds until fragrant, being careful not to burn it.
Pour in the chicken broth and scrape up any browned bits from the bottom of the pan. Let it simmer for 1-2 minutes to reduce slightly.
Stir in the heavy cream and parmesan cheese. Continue to simmer gently, stirring often, until the sauce thickens to a creamy consistency.
Add the sun-dried tomatoes and spinach. Cook for 1-2 minutes, just until the spinach wilts and the flavors meld.
Return the chicken to the pan, spooning some sauce over the top. Let everything simmer together for another 2-3 minutes so the chicken absorbs some of the flavors.
Taste and adjust the seasoning with more salt and pepper if needed. If the sauce thickens too much, add a splash of chicken broth to reach your preferred consistency.
Remove from heat and let rest for a couple of minutes before serving. This helps the juices redistribute and keeps the chicken juicy.