Heat a dry pan over medium flame and gently toast the fennel seeds until they release their aroma.
Place the fennel seeds along with the cinnamon stick, cloves, star anise and Indonesian long peppers into a mortar and pestle and grind until it forms a fine powder. Alternatively, place into a high speed blender and pulse until it reaches the desired consistency.
Place the remaining ingredients into a small saucepan over a medium heat along with all of the ground five spice powder. Bring to a simmer, stirring occasionally, and cook for five minutes.
Pour into hot sterilized jars and seal. Will keep for a few weeks in the fridge.