Every spectacular outdoor garden party or massive holiday family gathering demands a colorful centerpiece bake that actively celebrates the absolute height of seasonal fruit picking. This magnificent, large-scale traybake completely turns traditional pastry rules upside down by loading a rich, fluffy sponge floor with an incredibly generous mountain of fresh, glossy forest fruits. It is an exceptional selection for midsummer birthday bashes, corporate afternoon coffee hours, or festive weekend getaways when you need to serve 24 perfect squares with minimal hands-on effort. Spreading this vibrant masterpiece across your oven’s universal deep roasting pan fills your entire home with an absolutely hypnotic perfume of sweet vanilla and warm melted fats, automatically pulling everyone toward the kitchen counter.
The true culinary structural brilliance behind this highly satisfying summer creation relies heavily on a specialized dual-cushion dairy stabilization and a glassy protective gelatin mirror. Instead of defaulting to thin pudding layers or plain whipped creams, the smooth center achieves its incredible sämig density purely through a patient blend of thick vanilla custard and low-fat German Quark. Spreading this velvet cream evenly over the cooled sponge mattress ensures that the foundation remains perfectly supple while firmly anchoring a whopping 1 ¾ kilograms of raw red currants, blackberries, raspberries, and blueberries. It is a foolproof vintage blueprint that delivers a striking texture contrast, ensuring that every single slice yields a perfect combination of cloud-soft cake, tangy dairy, bursting fruit, and a clear sweet glaze.
What You Need
For The Fluffy Sponge Foundation
- 375 g unsalted butter (softened)
- 450 g white granulated sugar (divided)
- 1 packet aromatic vanillin sugar
- 1 pinch fine sea salt
- 6 medium farm-fresh eggs (Size M)
- 380 g all-purpose flour
- 100 g food cornstarch (Speisestärke)
- 3 tsp active baking powder
- Extra butter strictly for prepping the sheet pan
For The Velvet Custard Quark Cushion
- 800 ml whole milk (divided)
- 2 packets cook-style vanilla pudding powder
- 6 tbsp white granulated sugar
- 6 sheets premium white gelatin
- 750 g low-fat German Quark (Magerquark)
For The Fresh Berry Medley & Glassy Mirror
- 1 ¾ kg fresh mixed forest berries (such as red currants, blackberries, raspberries, and blueberries)
- 2 packets clear cake glaze powder (Tortenguss)
- 75 g white granulated sugar
- Plastic food wrap
Step-By-Step
Whisk together 100 milliliters of cold milk, both packets of vanilla pudding powder, and six tablespoons of sugar inside a glass cup until a completely smooth starch slurry develops. Bring the remaining 700 milliliters of whole milk to an aggressive rolling boil in a saucepan, pour in the starch slurry while stirring constantly, and cook for 1 minute until thick. Transfer the pudding into a bowl, press plastic food wrap directly across the damp surface to prevent a tough skin, and chill in the fridge for 2 hours. Drop 375 grams of softened butter, 375 grams of sugar, vanillin sugar, and salt into a spacious mixing bowl, whipping aggressively with your hand mixer for 5 minutes before adding your six eggs one at a time to build a rich cream.
Combine your all-purpose flour, food cornstarch, and active baking powder in a separate dry bowl, using a fork to whisk the powders into a level baseline. Fold this dry flour blend gently into your main butter cream until a smooth, thick sponge batter forms without any remaining flour pockets across your workspace. Generously grease a deep internal baking sheet pan measuring approximately 32 by 39 centimeters with extra butter, spread the heavy dough evenly across the bottom floor, and bake at 200°C for 35 to 45 minutes before letting it cool entirely. Soak your six gelatin sheets in a bowl of cold filtered water while you handle the remaining cold assembly elements.
Whisk your cooled vanilla pudding and 750 grams of low-fat German Quark together in a massive mixing bowl until an absolutely seamless, velvety dairy cream developments. Squeeze out your soaked gelatin sheets, dissolve them carefully over low heat in a small pan, stir in two tablespoons of the pudding cream, and then pour everything back into the main bowl. Spread this thick custard quark mixture uniformly over your cooled sponge floor, smooth the surface into a perfect mirror, and pile your 1 ¾ kilograms of fresh mixed berries high across the cushion before chilling for 4 hours. Whisk your clear cake glaze powder with 75 grams of sugar and a half-liter of water, bring to a boil, and ladle the fluid evenly over the berries to set. Dive in while it’s fresh!
Nutritional Breakdown (Per Individual Square Serving, Makes 24):
Energy: 390 kcal | Protein: 10 g | Fat: 17 g | Carbs: 48 g.
