How did this happen?! I left Copenhagen two weeks ago wearing shorts and a t-shirt and on my return had to pull out a down jacket for the morning bike ride to the office. During that same time, the market went from a veritable bounty of summer produce – mountains of tomatoes, peaches, green beans and berries – to neat stacks of pumpkins and apple crates. Somehow, Copenhagen seems to have skipped late summer and fast forwarded straight into fall. I’m not quite ready to let go of summer yet though. I wore sandals every day this week, despite torrential rain. And baked Zwetschgenkuchen.

Starting at the end of August and through September, you’ll find Zwetschgenkuchen, or plum tart, at bakeries and markets across German-speaking Europe. It’s a sheet cake made from a thin layer of either yeast dough or shortcrust pastry covered with prune plums. In Southern Germany, where I grew up, it’s called Zwetschgendatschi. In Switzerland they refer to it as Zwetschgenwähe. Traditionally, it’s made without streusel, but I love it best covered in a generous layer of crumbs. In some parts of Germany, it’s served together with potato soup for lunch or dinner, a practice I thoroughly endorse, because, well, after breakfast for dinner, the next best thing surely has to be dessert for dinner.

I had planned to dig out one of my mother’s recipes from an old German baking book, but by the time I returned to Copenhagen, she had left for a holiday in Canada. Instead I scoured the web for a suitable recipe. I couldn’t decide between the yeast and shortcrust version, so when I stumbled across a recipe that combined them both, I knew I had to try it. Frankly, the method is a bit odd – you make a small batch of yeast dough and shortcrust pastry and knead them together. But you can’t argue with the result: a perfectly buttery, flaky crust that’s solid enough to hold up to heavy cargo of fruit and crumble.

Zwetschgenkuchen aka Late Summer Plum Tart

Adapted from German food magazine essen & trinken.

Yeast dough:

80 ml (1/3 cup) milk

15 g (2 tsp) fresh yeast

1 tbsp sugar

1/2 tsp salt

125 g (1 cup) all-purpose flour

In a small saucepan, warm the milk until it is lukewarm. Transfer to the bowl of a stand mixer fitted with the dough hook and add the yeast, sugar and salt. Stir until the yeast is completely dissolved, then add the flour. Knead at medium speed until the dough is smooth. Cover and place the bowl in a warm place to let the dough rise for about an hour.

Shortcrust pastry:

50 g (1/4 cup) sugar

100 g all-purpose flour

1/2 tsp salt

75 g (5 tbsp) butter, cold, cut into 1-inch cubes

1 egg yolk

In a medium bowl, whisk together the sugar, flour and salt. Using a pastry cutter or a note, cut the butter and egg yolk into the dry ingredients until it resembles a mix of coarse crumbs and small chunks. Working quickly with your hands, press the crumbs together and knead lightly, until the pastry comes together. It will still be crumbly, but just press any stray crumbs back into the pastry. Wrap and place in the fridge for 45 minutes.

Meanwhile, make the crumb topping.

Crumb topping:

115 g (1/2 cup) butter, softened

150 g (3/4 cup) light brown sugar

100 g (1 cup) rolled oats

65 g (1/2 cup) all-purpose flour

1/2 tsp salt

In a medium bowl, combine butter and sugar and beat together until smooth. Stir in the oats, flour and salt and mix until fully incorporated. Place in the fridge to cool for 30 minutes.

To assemble the tart:

2 to 2 1/2 pounds of Italian (prune) plums, halved and pitted

2-3 tbsp of ground almonds

1/2 tsp cinnamon

Preheat the oven to 350 degrees F. Line and butter a 9 x13 inch sheet pan.

On a lightly floured surface knead together the yeast dough and shortcrust pastry. (I did this by folding the shortcrust pastry into the yeast dough, then folding and kneading until the dough was smooth and looked marbled.) Roll out the dough into a rectangle and transfer to the lined sheet pan, pressing the into all four corners. Sprinkle the crust with ground almonds.

Place the halved plums in tight rows, cut side up, covering the crust completely. Dust with cinnamon and sprinkle with crumb topping.

Bake for 40-45 minutes, until the crumbs are golden brown and the fruit is bubbling around the edges. Allow the tart to cool for about 30 minutes before serving. Serve with a generous dollop of whipped cream.

The tart can be stored, tightly covered, at room temperature or in the fridge, for 2-3 days. Makes one 9 x 13 inch sheet cake.