1Add the raspberries, sugar, and water into a pan.
2Cover with a lid, bring to a simmer, then cook over medium-low heat for 5-10 minutes until the raspberries have broken down. Mash with the back of a fork to help.
3Pour the raspberries into a fine mesh sieve and press through using the back of a spoon to remove the seeds.
4Place the strained couli back into the pan, add a squeeze of lemon juice, and cook for 5-10 more minutes until thickened.
5Leave to cool, chill, then serve on top of the cheesecake.