Add all ingredients to a blender and blend until smooth. (If you are concerned about the heat of your chili just use half of it and taste your sauce as it is cooking. If it isn't spicy enough, chop finely and add a little more).
Transfer to a pan and heat over a medium heat, stirring constantly until thick. It should take around 10 minutes.
Store Garlic Pineapple Sauce in a jar/sealed container in the fridge for up to 5 days or for up to 3 months in the freezer.