On a plate, mix flour with 1 Tbsp. rosemary, 1 tsp. salt and 1/2 tsp. pepper. Dredge chicken cutlets in seasoned flour; shake to remove excess.
Warm 2 Tbsp. oil in a large skillet over medium-high heat. Add cutlets and cook until golden, 2 to 3 minutes per side. Remove to a plate; cover loosely. Wipe out skillet, leaving behind browned bits.
Place skillet over low heat and warm 1 Tbsp. oil. Add garlic and 1 Tbsp. rosemary; stir for 1 minute. Add chicken broth and lemon zest and juice, scraping up browned bits on the skillet. Raise heat to medium; boil until sauce has thickened, about 5 minutes. Season with salt and pepper. Return chicken with juices to skillet, turning to coat. Serve hot.
Fantastic flavors, and super easy to make. If you're using lemon juice (or zest) from a bottle, I'd recommend not using the full amount suggested to replace 1 lemon. I made this mistake and man was that chicken lemony!