1. Whisk the cake flour and buckwheat flours, sugar, and salt in a large bowl to combine.
2. Add butter and work into dry ingredients with your hands, mashing it into big flat pieces and smooshing it between your palms into the flour, until you have pea-size pieces.
3.Drizzle ¼ cup ice water over mixture and rake it in with your fingers until evenly dispersed.
4.Squeeze the clumps with your hands to moisten until a shaggy dough forms, then turn out onto a work surface.
5. Gather dough together, pushing and working it into a ball, then flattening it, until only a few dry spots remain.
6. Pat into a thick square and using a bench scraper or knife, divide dough into 4 pieces. Stack pieces on top of one another, placing any unincorporated dry bits in between layers, and press down to combine.
7. Form dough into a thick disk and wrap tightly in plastic. Chill until firm, at least 2 hours and up to 3 days. Dough can be frozen for up to 3 months
1. Preheat oven to 200°C.
2. Roll out dough on a well-floured surface to approx 35 cm round, rotating dough and tossing more flour underneath as needed to keep it from sticking.
3. Transfer dough to a large baking paper-lined baking sheet (most galettes will spring a leak at the creases of the pastry, even for pros).
4 Place persimmon slices, cornstarch, and ⅓ cup sugar in a medium bowl. Scrape in vanilla seeds and discard pod; toss ingredients to evenly distribute.
5. Mound filling in the centre of the dough, making sure to scoop up all the sugar and cornstarch in bowl, and spread out, leaving a 5cm border around the edges. Fold dough up and over filling, overlapping slightly.
6. Brush dough with cream or egg wash and sprinkle dough and filling generously with the remaining sugar.
7. Bake galette until filling is bubbling and crust is deeply browned, 40–50 minutes. Let cool slightly. Serve topped with thick cream.
Recipe from Bon Appetit