Pat the chicken breasts dry with paper towels. Season both sides with salt and black pepper.
Heat the olive oil in a large skillet over medium-high heat until shimmering.
Add the chicken breasts to the skillet and cook for 5-6 minutes on each side, or until golden brown and cooked through (internal temperature should reach 165°F). Remove the chicken from the skillet and set aside on a plate.
Reduce the heat to medium. Add the minced garlic to the skillet and sauté for about 30 seconds until fragrant, stirring constantly to avoid burning.
Pour in the chicken broth and fresh lemon juice, scraping the bottom of the skillet with a wooden spoon to loosen any browned bits.
Stir in the unsalted butter and lemon zest. Let the sauce simmer for 2-3 minutes until slightly reduced.
Return the chicken breasts to the skillet, spooning the sauce over the top. Cook for an additional 1-2 minutes to warm the chicken through and allow flavors to meld.
Sprinkle the chopped fresh parsley over the chicken before serving.