Put the dry powders (flour, sugar and salt) + the cubed butter in the bowl of the food processor. Combine to obtain a slightly granular powder.
Add the egg yolk, mix, then 2 tablespoons water, mix until the dough forms a ball. Add a third spoon of water only if necessary.
Fold in plastic wrap and let it rest in the refrigerator for about 1 hour.
Poach peachs
Peel peaches and cut quarters.
Heat water with the verbena stem and the sugar. If you prefer, replace with mint or vanilla.
When the syrup boils add peaches, let it simmer for 3 minutes, turn off the heat and let infuse 10 to 15 minutes then drain.
Prepare galette
Preheat your oven to 180 °C.
Roll out pie crust, it doesn’t matter if it is not completely round.
Arrange the drained peaches leaving 2 cm all around. Add redcurrant here and there.
Fold the edges over fruits. Glaze the folded edges of dough with the beaten egg (or you may use cream).
Bake and dress
Bake for about 30 minutes, until the dough is cooked (variable time depending on the thickness of the dough).
Dress by adding fresh redcurrants when the tart has cooled down, before serving.
Notes
The main steps: Briefly poach peaches. Make short pastry, rest and roll out (or use ready-made). Garnish with drained peaches and redcurrants. Fold all around, glaze with beaten egg and bake.