Prep the chicken thighs. Remove the skin from the chicken thighs and then cut the thighs into 1 inch cubes. Heat the olive oil in a skillet over medium high heat. Add the chicken and cook for 5 minutes (or until no longer pink).
Prepare the sauce. Add the pineapple juice, chicken stock, hoisin sauce, soy sauce, cornstarch, chopped garlic cloves and brown sugar to a bowl and whisk until well combined.
Boil, add and cook. Pour the pineapple mixture into the skillet and bring to a boil. Add the pineapple chunks and stir to combine. Cook for a few minutes (or until the sauce has reduced and thickened to your liking).