I love this tart for a couple of reasons. First, it uses one of my favourite winterfruits, pomelo. Second, it's rather refreshing. This makes it not one of those hot apple pies you eat warm after stepping in from a cold winter day, but if you've been having a slightly warmer winter than usual (or you feel that despite going from home to classes/work every day, you've been nowhere but inside), perhaps you might not mind a refreshing tart. The sweetness may need to altered if you have a very sour yoghurt or a very sour pomelo, though I've had great luck with pomelos this year.
I'm afraid the recipe is a bit of a chore to read (gosh, isn't it?), but I'm fond of all the components! The crust is rolled out very thin to keep it delicate, and a thin layer of spongecake is baked right into the crust to act as a receptacle for the syrup. The syrup carries the rose and mint motif, followed by a layer of rich rosewater yoghurt, plenty of pomelo, and fresh mint leaves.
I need to credit the sweet pastry crust in Tartine by Elizabeth Prueitt and Chad Robertson for the proportions of the pastry. The sponge cake is adapted from a foolproof (so long as you beat the eggs enough!) Swiss cake roll recipe from NouraNi via the Cherry Share (http://www.thecherryshare.com/food/how-to-make-japanese-roll-cake-swiss-roll--1253). —tentimestea
1 9" tart
buckwheat pastry and almond sponge cake
soft unsalted butter, for the tart shell
kosher salt, for the tart shell
granulated sugar, for the tart shell
all-purpose flour, for the tart shell
buckwheat flour, for the tart shell
beaten egg (or 1/2 a large egg), for the tart shell
all-purpose flour, for the sponge
finely ground almond, for the sponge
large egg (50 g), for the sponge
icing sugar (confectioner's/powdered sugar), for the sponge
milk, for the sponge
rosewater, for the syrup
10% milk fat yoghurt, or a nice thick Greek yoghurt
Begin by making the pastry, using the ingredients marked "for the tart shell." Cream the butter with the sugar and salt. Add the flours and rub into the butter until everything is crumbly. Add the egg and squish together until evenly mixed and it forms a cohesive dough. Wrap in plastic and chill.
Preheat the oven to 375F.
Roll out the chilled dough on a floured surface quite thinly (1/8" thick) and line a 9" tart pan. It's a bit delicate so you may have to transfer the dough in pieces and press them together. Line with a piece of parchment paper, fill with a baking weight (for example, I use around 1 cup uncooked rice), and blind bake for 20 minutes.
Remove the parchment and baking weight. If the pastry still appears a bit moist, you can bake it for another few minutes.
While the pastry is baking, begin to work on the spongecake. It uses the remaining ingredients, marked as "for the sponge." Whisk together the flour, ground almond, and salt.
Beat the egg until frothy, then add the icing sugar and beat until thick and white. The eggs will have more than doubled in volume. The eggs will not hold any peaks, but when a bit the egg mixture is dripped from a whisk onto the top, it will stay there for a good second or so before melding back into the eggs in the bowl.
Sift the flour mixture over top (add in any almonds that do not pass through the sieve) and fold in. Fold in the milk.
Scrape the batter onto the warm and baked tart shell and continue to bake at 375F for 10-15 minutes or until the cake is lightly browned on top.
Let cool on a wire rack.
Begin by making the syrup to brush onto the spongecake layer in the tart shell. Put the water and granulated sugar in a small saucepan and heat until boiling. Roll the mint sprigs in your hands until they are well bruised, then add to the water. Cover and remove from the heat and let steep for seven minutes. Pull out the mint sprig and 3/16 tsp rosewater, or to taste depending on the strength of your rosewater.
Next, make the yoghurt. Whisk the yoghurt with a bit of icing sugar to sweeten (you may want to add more or less to taste) and the 1/2 tsp of rosewater (or to taste).
Then, prepare pomelo assembly. Peel the membrane from the pomelo segments and remove the seeds. Break the segments into smaller pieces.
Finally, assemble. Lightly brush the rose and mint syrup over the cooled sponge--you will only use a bit. Let soak in before spreading the rosewater yoghurt over the sponge. Arrange the pomelo over the yoghurt, scatter with a generous quantity of mint leaves and a few dried rose petals if desired.