Brining means putting it in saltwater for some time. Makes everything better.

• Boneless, Skinless Chicken breasts (up to 6 breasts): Mix 1½ quarts (~1.5 L.) cold water with 3 tablespoons table salt; brine ½ to 1 hour. ¹
• Simple Chicken Brine Recipe | Allrecipes

Really nice simple recipe that includes brining: Baked Chicken Breast | Gimme Some Oven

• 230C, 15-18 min