Pat chicken dry. Season all over with salt and pepper.
Heat olive oil in a large skillet over medium-high heat.
Sear chicken until golden, 3–4 minutes per side. Transfer to a plate.
Reduce heat to medium. Melt butter, then sauté garlic for 30 seconds.
Pour in broth. Scrape up browned bits and simmer 2 minutes to reduce slightly.
Stir in cream and pesto. Simmer gently until slightly thickened, 3–4 minutes.
Return chicken and any juices to the pan. Cover and cook until 165°F, 6–8 minutes.
Fold in Parmesan, lemon juice, and red pepper flakes until smooth.
Stir in spinach and tomatoes. Cook until spinach wilts, 1–2 minutes.
Rest 3 minutes off heat. Spoon sauce over chicken to serve.
Notes
Serve over buttered pasta, gnocchi, or zucchini noodles. For a richer sauce, swap half the broth for more cream. Use chicken thighs instead of breasts if you prefer; add 2–3 minutes to the simmer time. Leftovers keep 3 days chilled; rewarm gently with a splash of broth.This recipe is an original creation inspired by classic Creamy Garlic Pesto Chicken Recipe flavors. All ingredient ratios and instructions are independently developed.