Place the chicken thighs, stock, onion powder, garlic powder, salt and pepper in a slow cooker.

Cook on low for 4 hours until the chicken shreds easily with two forks.

Remove the chicken and shred it finely, discarding any tough bits.

Pour the cooking liquid into a saucepan, bring to a simmer, and stir in the cornflour mixture to thicken into a gravy.

Return the shredded chicken to the gravy and stir through until well coated and moist.

Serve warm.