Pound each chicken breast between two sheets of plastic wrap or in a resealable bag until about 1.5 cm thick, ensuring they are even for uniform cooking. Lightly season with salt and pepper.
In a shallow dish, combine the grated Parmesan, minced garlic, and red pepper flakes if using, then mix thoroughly to distribute the flavors evenly.
Dredge each chicken breast in the Parmesan mixture, pressing gently to help the crust stick evenly on all sides, then set aside.
Heat the olive oil in a large skillet over medium-high heat until it shimmers and begins to gently smoke, signaling it's hot enough for searing.
Carefully place the coated chicken breasts into the hot skillet, laying them down away from you to avoid splashes. Sear for about 4-5 minutes until the crust is golden brown and crispy.
Flip the chicken using tongs and cook for another 4-5 minutes until the crust is deep golden and the internal temperature reaches 75°C (165°F), with juices running clear.
Once cooked, transfer the chicken to a plate and let it rest for about 3 minutes, allowing the juices to redistribute for maximum juiciness.
Squeeze fresh lemon juice over the rested chicken to brighten the flavors and sprinkle with extra Parmesan if desired for added richness.
Serve immediately with your favorite sides, enjoying the crispy crust and fragrant, tender interior in every bite.
