Wash and pat dry the chicken breasts. On a plastic cutting board, using a sharp knife, cut the breasts in half to make 4 thin cuts. Using clean hands, sprinkle about 1 tsp of kosher salt onto each side of the breast. If you’re using a denser salt like sea salt or Morton's, halve the amount.
Tightly wrap the chicken in plastic wrap and move to the refrigerator until you’re ready to cook—a few hours, or up to 2 days.
To cook, heat about 1 Tbsp of olive oil per breast over medium-high heat. When the oil shimmers, gently place the breast into the skillet and sear until browned. Reduce the heat to medium, and continue cooking until the bottom half of the breast is cooked about 3/4 of the way—5-6 minutes. Flip the breast and continue cooking for another 3-4 minutes, or until the internal temperature reads 165 degrees F. Remove chicken from heat and allow to rest for a few minutes before serving.