Prepare the Chicken: Begin by setting your crockpot to the high heat setting. Place fresh or thawed chicken breasts at the bottom of the pot, ensuring they are laid out evenly.

Add the Flavorings: Pour a generous amount of your favorite barbecue sauce over the chicken breasts, ensuring they are fully covered. Sprinkle in the brown sugar and scatter the chopped yellow onion on top.

Coat the Chicken: Using tongs or a spatula, gently turn the chicken breasts to coat them thoroughly in the barbecue sauce and seasonings.

Cooking Time: Cover the crockpot with its lid and cook the mixture on high for about 4 hours, or 6-7 hours on low.

Shred the Chicken: Once cooking is complete, uncover the crockpot and transfer the chicken breasts to a large bowl. Use two forks to shred the chicken, mixing it back into the sauce and onions.

Assemble Your Sandwiches: Grab your sturdy sandwich buns and generously spoon the shredded chicken mixture onto the bottom half of each bun.