- Prep chicken: Pound the chicken breasts to an even thickness. Season both sides with salt and pepper. 
- Sear chicken: Heat olive oil in a large pan over medium-high heat. Sear chicken for 3-4 minutes per side until golden brown. Remove and set aside. 
- Make sauce: In the same pan, sauté garlic for 1 minute. Add chicken broth, lemon juice, and zest, scraping browned bits from the pan. Simmer for 2 minutes. 
- Add cream & cheese: Stir in heavy cream and Parmesan cheese. Simmer until sauce thickens slightly. 
- Wilt spinach: Add fresh spinach and cook until wilted, about 1 minute. 
- Combine & cook: Return chicken to pan, spoon sauce over, cover, and cook on low 8-10 minutes until chicken reaches 165°F internally. 
- Serve: Garnish with parsley and lemon slices. Serve hot.