On the East End of Long Island, September is the season of mild temperatures and low humidity, bountiful harvests at local farms, and the greatly anticipated exodus of summer’s tourists. It’s also the season for prune plums; that wonderful small, purple-black fruit which begs to be eaten by the handful, or to be used in a number of different desserts. One of my favorites is a plum tart. Our friend Ilse had just returned from a family visit to Germany. In addition to bringing us food goodies from Europe, she whipped up a plum tart to share with us before she came over to our kitchen to catch up on what she had missed here at summer’s end. I had almost forgotten that it was plum time, and inspired by a tip she gave me for cutting the plums, I made a couple of plum tarts over the following few days.
My go-to pie or tart crust is, invariably a pâte brisée. For my plum tart, however, I chose to use a pâte à sucre crust instead. My feeling was that a “cookie dough” crust would be more impervious to the plum juice released during baking, and it would remain more crunchy. And that’s certainly true, especially if you enjoy the tart the day it’s baked.
Over my baking career, I’ve tried many pâte à sucre formulas. My first was one from Julia Child; since then I’ve settled on Rose Beranbaum’s formula from The Pie and Pastry Bible. It’s easy, it’s forgiving if you have trouble transferring it from rolling it out and moving it into the tart form or pie plate, and it’s deliciously crisp and crunchy with just a hint of sweetness.
Pâte à sucre:
Unsalted butter 113 g (8 Tbsp)
sugar 50 g (¼ cup)
salt 1/8 tsp
egg yolk 18 g (1 large)
heavy cream 28 g (2 Tbsp)
Although you can make this by hand, I always use a food processor for making pastry dough. So, with a food processor fitted with its metal blade, blitz the butter and sugar between 15 and 20 times until the two are well combined. Add the salt and flour and blitz it again 15 to 20 times, until the mixture resembles small peas. In a small bowl beat the egg yolk and the cream together until well blended, and add it to the food processor work bowl containing butter and sugar. Pulse until amalgamated.
Transfer the dough into a gallon size zip lock bag. Squeeze out the air and knead the dough with your fingers, working it into a 5 or 6 inch disc. Once you form the doughy disk, remove it from the plastic bag and wrap it tightly in a piece of plastic wrap. Refrigerate it for about 30 minutes.
For the Plums:
Cornstarch 1 tsp
Prune Plums 2 ¼ lbs
Sugar 50 g (¼ cup)
Ground cinnamon ½ tsp
Nutmeg ¼ tsp
Apricot preserves ½ cup
Cointreau 1 ½ oz
While the dough was chilling in the fridge, I washed and de-stemmed the plums. Employing my friend Ilse’s prep tip, I took a sharp pairing knife and sliced each plum, starting from the stem end, continuing down to the bottom portion of the plum and around to the opposite side. The trick is not to cut all the way through but rather stop at around a quarter of the way up the back side. Then I went back to the stem end and cut the unsliced end a quarter of the way down. The idea is to open the plum like a book, leaving a scant “hinge” of flesh and skin on one side of the pit.
Remove the pit and carefully cut each of the to halves into two slices, again leaving a hinge on the back side of each half. You now have four plum slices that are still connected. Continue slicing and pitting the rest of the plums. After three or four plums, you’ll be an expert and the entire process will take you less than ten minutes. The key to this is a sharp knife. When you’re finished set the bowl of plums aside.
After thirty minutes, remove the pastry dough from the refrigerator and unwrap it. Here’s where a little experience with pâte à sucre helps. You’re looking for a dough that is cold yet still malleable. There are several schools of thought on how to roll out a pâte à sucre. Interestingly, one is not to refrigerate the dough but to put it in the freezer, and then grate it into the form and shape it into a crust with your fingers, basically shaping the shavings into a crust shape. Another is to roll it out between two pieces of plastic wrap, then remove the top layer, position the tart form over it upside down, and quickly invert it. My method is to flour a pastry cloth and a rolling pin. Place the chilled dough on the pastry cloth, and roll it out about 1/8 inch thick. The dough will crack and separate around the edges. Push it together with your fingers, and gently persuade it together with your pin. Don’t be shy about using additional flour on the dough and your pin. When you have it rolled out the size that will exceed the size of your form, take a pot, pan or whatever is handy that is slightly larger than the size of the tart form, and slip it under the pastry cloth that still has the expanded dough on it. Place the form upside down over the dough and gently lay it on top. Then carefully and quickly invert the pan, the pastry cloth and dough, and the form. Voilà!
Well, hopefully. If the dough cracked over the edges or the form cut the dough, no worries. Here’s the cool thing about pâte à sucre: it’s easy to fix and repair cracks and tears because once it’s baked, it’s going to look perfect.
Now take the dough in the form, and blind bake it in a preheated 350 degree oven for 10 minutes. To blind bake, place a piece of parchment paper to line the dough in the form and weight it down with dried beans or ceramic pie weights. After ten minutes, or when the exposed edge crust starts to turn golden, remove from the oven.
First sprinkle with the cornstarch; I put the cornstarch in a small hand held sieve and coat the dough. Now get those plums that you so carefully cut and start leaning the first course standing up on one end, around the inside edge of the crust. Continue in concentric circles until you reach the center. If you have gaps along the way, don’t hesitate to use a single or two plum sections. Sprinkle the cinnamon (preferably fresh), follow with the nutmeg (preferably freshly grated), and finally the sugar and the Cointreau. Place the tart back in a 350 degree oven for 45 minutes. After 35 minutes, take a peek; the crust edge should be nicely golden brown and the tips of the plums should be just slightly singed. If not, let it bake for the full 45 minutes.