First of all, remove all the seeds.

You should remove all the fiber around the seeds.

Then, remove the peel and cut the pumpkin flesh into lozenge pieces.

Place as much water in a bowl as is needed to cover the pumpin pieces thoroughly, dissolve 2-3 tbsp pickling lime in it and set it aside for 2-3 hours.

Rinse the pumpkin pieces thoroughly with plenty of water, discarding it and using fresh for each rinse.

Boil the pumpkin pieces in plenty of water.

When it starts to boil, I always discard this water and use fresh to make sure that there is no residue of pickling lime left.

Using fresh water, boil the pumpkin pieces until they are almost tender.

Empty them in a strainer to strain and prepare the syrup.

Use1 1/2 kg of sugar and about 2 1/2 cups water (the pumpkin will let out some liquids as well) per 1 kg of pumpkin. Boil the water with the sugar for about 5 minutes and add the piece to the syrup. Let everything boil together until the syrup thickens. Meanwhile, while boiling, don't forget to skim off the foam.

Towards the end add the vanilla and 1 tsp citric acid.

Let it boil for a couple of minutes more.