Quick Recipe Version (TL;DR)
Quick Ingredients
- 500 g (about 4 cups) all-purpose flour
- 75 g (6 tbsp) sugar; 7 g (2¼ tsp) instant yeast; 1 tsp fine salt
- 240 g (1 cup) warm whole milk, 2 large eggs, 85 g (6 tbsp) unsalted butter, 1 tsp vanilla
- 1 kg (2.2 lb) Italian prune plums, halved; 2 tbsp sugar; 1 tbsp lemon juice; 1½ tbsp cornstarch; ½ tsp cinnamon
- Streusel: 150 g (1¼ cups) flour; 100 g (½ cup) sugar; 50 g (¼ cup) light brown sugar; ½ tsp cinnamon; ¼ tsp salt; 115 g (½ cup) cold butter; 1 tsp vanilla
- Optional: ⅓ cup sliced almonds; apricot jam; confectioners’ sugar
Do This
- 1. Make dough: Combine warm milk, sugar, yeast, eggs, vanilla, salt, and flour; knead, then work in butter until smooth.
- 2. First rise: Cover and let double, 60–75 minutes.
- 3. Prep plums: Toss with sugar, lemon, cornstarch, and cinnamon; set aside. Mix streusel to coarse clumps.
- 4. Pan: Grease a 13×18-inch sheet pan. Press dough evenly into pan.
- 5. Top: Arrange plums cut-side up in rows; sprinkle on streusel (and almonds).
- 6. Proof 20–30 minutes, preheat to 375°F/190°C, bake 30–35 minutes until golden and bubbly. Cool, glaze or dust.
Why You’ll Love This Recipe
- Classic bakery-style German sheet cake with a tender, buttery yeasted base.
- Juicy Italian prune plums bake into jammy pockets under a crunchy cinnamon streusel.
- Feeds a crowd and slices cleanly for potlucks, picnics, or afternoon coffee.
- Make-ahead friendly: dough, fruit, and streusel can be prepped in advance.
Grocery List
- Produce: 1 kg (2.2 lb) Italian prune plums, 1 lemon
- Dairy: Whole milk, unsalted butter, 2 large eggs
- Pantry: All-purpose flour, granulated sugar, light brown sugar, instant yeast, cornstarch, ground cinnamon, vanilla extract, fine sea salt, apricot jam (optional), confectioners’ sugar (optional), sliced almonds (optional)
Full Ingredients
Yeasted Dough
- 500 g all-purpose flour (about 4 cups, spooned and leveled)
- 75 g granulated sugar (6 tbsp)
- 7 g instant yeast (2¼ tsp)
- 1 tsp fine sea salt
- 240 g whole milk (1 cup), warmed to 110°F/43°C
- 2 large eggs, room temperature
- 85 g unsalted butter (6 tbsp), softened
- 1 tsp vanilla extract
- Optional: 1 tsp finely grated lemon zest
Plum Layer
- 1 kg Italian prune plums (about 2.2 lb), halved and pitted
- 25 g granulated sugar (2 tbsp)
- 1 tbsp fresh lemon juice
- 12 g cornstarch (1½ tbsp)
- ½ tsp ground cinnamon
Streusel Topping
- 150 g all-purpose flour (1¼ cups)
- 100 g granulated sugar (½ cup)
- 50 g light brown sugar (¼ cup, packed)
- ½ tsp ground cinnamon
- ¼ tsp fine sea salt
- 115 g cold unsalted butter (½ cup, 1 stick), diced
- 1 tsp vanilla extract
- Optional: 40 g sliced almonds (about ⅓ cup)
To Finish
- 2 tbsp apricot jam, warmed with 1 tsp water (optional glaze)
- Confectioners’ sugar, for dusting (optional)
- Butter or neutral oil, for greasing the pan
Step-by-Step Instructions
Step 1: Make the dough base
In the bowl of a stand mixer, whisk the warm milk (110°F/43°C), sugar, and instant yeast. Add the eggs, vanilla, and salt; whisk to combine. Add the flour and mix with a dough hook on low until a shaggy dough forms, 1–2 minutes.
Step 2: Knead and add butter
Knead on medium speed until the dough starts to look smooth, 4–5 minutes. With the mixer running, add the softened butter in 3–4 additions, letting each incorporate before adding the next. Continue kneading until the dough is silky, elastic, and pulls from the bowl (it will be soft), about 3–5 minutes more. If kneading by hand, expect 8–10 minutes total. The dough should pass a gentle windowpane test.
Step 3: First rise
Scrape the dough into a lightly greased bowl, cover tightly, and let rise in a warm, draft-free spot until doubled, 60–75 minutes. A clear, lidded container helps you gauge volume.
Step 4: Prepare the plums
While the dough rises, toss the halved plums with sugar, lemon juice, cornstarch, and cinnamon. Set aside; their juices will slightly thicken as they sit. For a classic look, you can slit each plum half lengthwise into thirds without cutting through and fan them slightly.
Step 5: Mix the streusel
In a medium bowl, whisk the flour, granulated sugar, brown sugar, cinnamon, and salt. Add the cold diced butter and vanilla. Rub with fingertips or pulse in a food processor until sandy with pea-sized clumps. Fold in sliced almonds if using. Refrigerate streusel until needed.
Step 6: Pan and assemble
Grease a 13×18-inch rimmed sheet pan (half-sheet) or line with parchment. Turn the risen dough onto the pan and press it evenly to the edges; if it springs back, rest 5 minutes and continue. Arrange plums cut-side up in tight rows, slightly overlapping. Scatter the chilled streusel evenly over the fruit.
Step 7: Second proof and preheat
Let the assembled cake rise, uncovered, for 20–30 minutes while you preheat the oven to 375°F/190°C with a rack in the center. The dough should look slightly puffy around the fruit.
Step 8: Bake, cool, and finish
Bake until the streusel is deep golden and the plum juices bubble thickly, 30–35 minutes (target 32 minutes). Rotate the pan once halfway for even color. Cool on a rack for at least 30 minutes. Brush with warm apricot jam for sheen or dust with confectioners’ sugar just before serving. Slice into 16 squares.
Pro Tips
- Use Italian prune plums if possible; they bake jammy without turning watery. If using larger plums, cut into thick wedges and pat dry.
- Chill the streusel so the butter stays cold; this ensures crisp, distinct crumbs.
- For a taller, breadier base, reduce pan size to 12×17 inches and add 5 minutes baking time.
- If your kitchen is cool, proof the dough in the oven with the light on and a mug of hot water on the rack below.
- Brush with warm apricot jam to lock in moisture and give a classic bakery gloss.
Variations
- Cardamom Streusel: Replace cinnamon with ½ tsp ground cardamom and add 1 tsp orange zest to the dough.
- Almond-Marzipan: Dot 75 g (2½ oz) grated marzipan over the dough before adding plums; top with almond streusel.
- Stone Fruit Mix: Use a mix of prune plums and sliced nectarines or apricots; keep total fruit to about 1 kg and pat very juicy fruit dry.
Storage & Make-Ahead
Store cooled cake, covered, at room temperature for up to 2 days. For longer storage, refrigerate up to 4 days; rewarm slices at 300°F/150°C for 8–10 minutes to re-crisp the streusel. Freeze tightly wrapped squares for up to 2 months; thaw at room temperature and refresh in a warm oven. Make-ahead: Mix the streusel up to 3 days ahead (refrigerate). Toss plums up to 4 hours ahead (refrigerate). The dough can be made the day before; after the first rise, punch down, cover, and refrigerate overnight. Bring to room temperature (45–60 minutes), then shape, top, proof, and bake.
Nutrition (per serving)
Approximate values per 1 of 16 pieces: 360 calories; 15 g fat; 54 g carbohydrates; 5 g protein; 2 g fiber; 210 mg sodium; 24 g sugars.
