Deseed & soak the Kashmiri red chillies, cut the stalk of the chilli using a pair of scissors & then split the chilli by cutting it through the middle length wise, majority of the seeds will fall off & the remaining will get separated from the chillies while soaking.
Transfer the chillies into a bowl & pour hot water until they are completely submerged, cover & soak for 40 minutes to 1 hour at least.you can also boil the chillies for 20-25 minutes if you want to skip the soaking step. Now transfer them in a mixer grinder jar & grind them into a very fine paste using minimal amount of water.
In a wok heat oil on medium to high flame ,add star anise, garlic, ginger & celery, stir & cook on high flame until the garlic turns golden brown, this process will take upto 4-5 minutes.
Once the garlic has turned golden brown, add the red chilli paste that you made along with green chilli paste .
Cook for 10-15 minutes while stirring frequently, the colour of the chutney should darken & its texture should become crumbly.
Add ketchup, red chilli sauce, soy sauce, vinegar ,salt ,sugar and white pepper powder. Stir well & cook for 3-4 minutes, you don’t have to cook a lot at this stage because you have already cooked the chillies & the sauces that you have added are already cooked.
Check for seasoning at this stage & adjust salt accordingly.Your schezwan chutney is ready, cool it down completely before transferring it into an airtight container, you can store & use it upto 1-1.5 months if refrigerated.