01 - Pat the chicken breasts dry with paper towels. Season both sides generously with salt and black pepper. Lightly dredge each breast in flour, shaking off any excess coating.
02 - Heat olive oil in a large skillet over medium-high heat until shimmering. Add chicken breasts and sear for 4–5 minutes per side until golden brown and cooked through to internal temperature of 165°F. Transfer chicken to a plate and set aside.
03 - Reduce heat to medium. Add butter and minced garlic to the same skillet. Sauté until fragrant, approximately 1 minute, being careful not to burn the garlic.
04 - Stir in sliced sundried tomatoes and cook for 1 minute to release their flavors. Pour in chicken broth and bring to a gentle simmer, using a wooden spoon to scrape up any browned bits from the bottom of the pan.
05 - Add heavy cream and grated Parmesan cheese. Stir continuously until the cheese completely melts and the sauce thickens slightly, about 3–4 minutes. The sauce should coat the back of a spoon.
06 - Add fresh baby spinach to the sauce. Cook for 1–2 minutes until just wilted, stirring gently to incorporate.
07 - Return chicken breasts to the skillet, spooning the sauce generously over the top. Simmer for 3–4 minutes to heat the chicken through and blend the flavors. Garnish with chopped fresh basil if desired. Serve immediately while hot.