Place chicken breasts in the slow cooker in a single layer
Season with salt, pepper, and any desired spices or sauce
Add a small amount of liquid such as broth, water, or sauce
Cover and cook on low for 3 to 4 hours or on high for 1.5 to 2.5 hours
Check for doneness with a thermometer; internal temperature should reach 165°F
Avoid overcooking to keep the chicken moist
Let the chicken rest for a few minutes before serving or shredding