You may substitute regular plums in this recipe, but the smaller Italian prune plums are sweeter. This is a great cake to make for breakfast, because the dough rises overnight in the refrigerator.
1/3 cup lukewarm water
1 package (2-1/4 teaspoons) dry active yeast
1 tablespoon granulated sugar
2-1/3 cups all-purpose flour, divided, plus extra for work surface
3/4 teaspoon plus 1/2 teaspoon table salt, divided
1 large egg
1 stick (8 tablespoons) plus 2 tablespoons unsalted butter, at room temperature
12—14 Italian prune plums or 9 regular plums
1/2 cup firmly packed light-brown sugar
1/2 cup blanched almond slices, lightly crushed
In a small bowl, whisk together warm water and yeast; set aside. Put sugar, 2 cups flour, 3/4 teaspoon salt, egg, and 1 stick butter in the bowl of a mixer or food processor fitted with a dough blade. Add yeast mixture and pulse until a ball forms. It should be sticky; add more water, a tablespoon at a time, if needed. Remove dough from processor and transfer to a lightly oiled bowl. Cover with plastic wrap and refrigerate overnight. It will rise only slightly.
When dough is ready, adjust oven rack to middle position and preheat to 400°. Remove dough from refrigerator and set aside. Halve plums (if using regular plums, cut into quarters) and remove stones; set aside.
Prepare crumb topping: In a small bowl, combine 1/3 cup flour, 1/2 teaspoon salt, 2 tablespoons butter, and brown sugar. Rub mixture with your fingers until crumbly; then stir in almonds and set aside.
Grease a 9-inch springform pan. Remove dough from bowl and, on a lightly f loured work surface, press with your fingers into a 9-inch circle. Place dough in pan. Leaving a 1/2-inch border around edge of dough, arrange plums snugly, like fallen dominoes, in circles over surface of dough.
Sprinkle crumb topping on plums; then bake until topping and crust are light brown and plum juices run, 40—45 minutes.
For total preparation time include at least 6 hours rising time.