Gather all your ingredients: chicken thighs, pearl barley, carrots, onion, garlic, fresh thyme, chicken stock, salt, pepper, and lemon. Prepare a chopping board and knife for chopping and mincing.
Peel and chop the carrots into thick chunks, dice the onion, and mince the garlic. These fresh vegetables will cook down and sweeten during slow simmering.
Place the chicken thighs at the bottom of the slow cooker. Spread the chopped carrots, diced onion, minced garlic, and thyme sprigs on top, creating a colorful layer.
Pour the chicken stock over the ingredients, ensuring everything is submerged or evenly covered. Season generously with salt and pepper for a flavorful base.
Sprinkle the rinsed pearl barley evenly over the top, spreading it out to prevent clumping. Cover the slow cooker with its lid.
Set the slow cooker to low heat—around 90°C or 195°F—and cook for 6 to 8 hours. During cooking, the house will fill with a warm, savory aroma.
After about 6 hours, check if the chicken has fallen apart easily and the barley is tender but retains a slight chew. If needed, cook longer, up to 8 hours, for more developed flavors.
Remove the chicken thighs and shred the meat with two forks. Return the shredded chicken to the pot and stir well to distribute evenly.
Taste the soup and adjust the seasoning with more salt, pepper, or a squeeze of lemon juice for brightness. Stir gently to incorporate the flavors.
Let the soup rest uncovered for 10 minutes to deepen the flavors and allow excess steam to escape. Serve hot, garnished with fresh herbs or lemon wedges if desired.
