For the pastry
1. In a stand mixer, beat butter and icing sugar till smooth, at medium speed.
2. Add eggs and mix well.
3. At low speed, add flour and almond powder, mix briefly until a dough is formed. Wrap & chill dough for 1 hour.
4. On a lightly floured surface, roll out dough to 3mm-thick.
5. Use a 10cm round cutter to stamp out rounds of dough. Using fingers, neatly press each dough disc into a 8cm tart ring. Repeat with the other three pieces.
6. Fill tart shells with rice or beans to weigh them down. Bake tart shells at 165°C for 15 minutes, or until golden-brown. Remove beans or rice if using. Allow to cool completely on a rack.
For the yuja cream
1. Combine yuja jam and milk in a pot and bring mixture to a slow boil over medium-low heat, stirring constantly. Remove pot from the heat the moment mixture boils (don’t let it cook, as the mixture will be used immediately after step 3).
2. In a mixing bowl, whisk sugar and egg yolks together till smooth, the stir in the corn starch till thoroughly incorporated.
3. Slowly pour the boiled yuja jam and milk into the egg yolk mixture, constantly whisking to combine.
4. Pour everything back into the pot and bring to a boil. Cook on medium heat for 7 minutes, or until mixture thickens.
5. Add the butter and whisk.
6. Pour cream mixture onto a tray, wrap tightly with cling wrap so surface of cream is in contact with plastic (so a film doesn't form). Store in fridge until completely chilled.
7. Soften chilled cream by stirring it in a mixing bowl before using.
Assembly
Fill a piping bag with the softened yuja cream. Fill each baked tart shell with the cream, dividing the amount evenly between the four shells.
Using a sharp knife, carefully slice each grape into half and arrange on top of each tart in a concentric pattern.
Gently brush grapes with apricot glaze and chill 30 mins before serving.