Preheat the oven to 125 C.

Cut the peaches in half, discard the stones, then bring the sugar, water and thyme to a boil. Place the peaches into the syrup and simmer until soft. Transfer to a blender and blend until smooth. Pass the syrup through a sieve and reserve 60 g for the gel.

Add peach puree, reserved syrup and water to a saucepan and bring to a boil. Combine sugar with pectin and whisk in while bringing back to a boil. Add citric acid and remove from heat. Blend until smooth and pass through a sieve. Allow to cool and set until firm.

Place cream, cream cheese, sugar and umeshu in a saucepan and bring to a simmer. Remove from heat. Temper the egg yolks by whisking in the hot cream mixture. Add remaining cream mixture and blend until shiny and smooth, then strain through a sieve into a jug.

Spread dulce de leche over the pastry shell base. Pour custard on top of the caramel layer. Bake for 30 minutes until slightly wobbly in the centre, then allow to cool.

Melt white peach gel over low heat. Pour into tart in a circular motion, starting from the inside and move outwards. Allow to set in the fridge.

Once set, remove tart from tin and portion into slices with a hot sharp knife.