Preheat the oven to 400°F (200°C).
Pat the chicken breasts dry with paper towels and season both sides generously with salt and black pepper.
Heat the olive oil in an oven-safe skillet over medium-high heat and sear the chicken for 2 to 3 minutes per side until golden brown.
Transfer the skillet to the oven and bake for 18 to 20 minutes, or until a food thermometer inserted into the thickest part reads 165°F (74°C).
Let the chicken rest for 5 minutes before slicing to keep juices sealed inside.
Why This Recipe Works: Searing chicken in olive oil first locks in moisture before transfer to a 400°F oven. This two-stage cooking method ensures juicy boneless chicken breast every time without drying out.
Storage & Make-Ahead Tips: Refrigerate cooked chicken in an airtight container for up to 4 days. Reheat gently in a skillet or oven at 350°F with a splash of broth to retain moisture.