Start by patting the chicken breasts dry with paper towels, then pound them to an even thickness of about 2 cm (0.8 inch) using a meat mallet or rolling pin. Season both sides lightly with salt and pepper.
Heat a large skillet over medium heat and add a tablespoon of olive oil, swirling to coat the bottom. Once the oil shimmers and is hot, carefully place the chicken breasts in the pan, laying them away from you to avoid splatters.
Sear the chicken without moving for about 6-7 minutes, until the bottoms are golden brown and release easily from the pan. Flip the chicken using tongs and cook for another 6-7 minutes on the other side until the chicken is golden and cooked through.
Reduce the heat to medium-low, cover the skillet loosely with a lid or foil, and cook for an additional 8-10 minutes, or until a meat thermometer inserted into the thickest part reads 75°C (165°F). The chicken should feel firm and juices run clear.
While the chicken cooks, whisk together honey, Dijon mustard, minced garlic, and lemon juice in a small bowl until smooth and combined. The sauce should be bright and slightly thickened.
Remove the lid, increase the heat slightly, and pour the honey mustard sauce over the chicken breasts in the skillet. Cook for 2-3 minutes, spooning the sauce over the chicken as it bubbles and thickens into a shiny glaze.
Once the sauce is glossy and thick enough to coat the back of a spoon, check that the chicken has reached the proper internal temperature. Remove from heat and let the chicken rest for about 3 minutes to reabsorb juices.
Slice the chicken if desired, spoon additional sauce from the skillet over the top, and serve hot with your favorite sides. The glaze should be sticky, caramelized, and flavorful, with a beautiful sheen.
