Apfelstrudel — Viennese apple strudel

i. Origin & history

Apfelstrudel is so closely identified with Vienna that it has become a symbol of Austrian cooking, but the pastry behind it has roots further east. Stretched, layered doughs were known across the Ottoman world, and the common story is that the technique came to the Habsburg lands by way of Hungary, where Ottoman rule lasted through much of the sixteenth and seventeenth centuries. The details are hard to prove, but the kinship with filo pastry is clear.

The oldest known strudel recipe is usually said to be a handwritten one from 1696, kept in the Vienna City Library, and it is for a milk-cream strudel rather than an apple one. Apple strudel became the favourite over the following centuries, as orchards around Vienna and throughout Austria supplied cheap, sharp cooking apples, and by the nineteenth century it was an established part of the city's confectionery and of the imperial kitchen. Today it is on almost every Austrian café and restaurant menu, and in Bavaria and South Tyrol as well.

The word Strudel means whirlpool or eddy in German, describing the spiral of thin pastry layers and filling you see when the strudel is cut. Apfel means apple, so Apfelstrudel is simply 'apple whirlpool' or apple strudel. In Hungary the same pastry is almás rétes, in Czechia jablečný závin, and in Slovenia jabolčni zavitek.

Apfelstrudel is often compared with its sibling Topfenstrudel. Both use the same stretched dough; the difference is the filling. Apfelstrudel is filled with apples, raisins, cinnamon and buttered breadcrumbs and is fresh and fruity; Topfenstrudel is filled with sweetened quark (Topfen), eggs and lemon, and is creamy and custard-like, often baked in a dish with milk poured over.

ii. What the buttered breadcrumbs do

A good Apfelstrudel depends on keeping a very thin, crisp pastry dry around a very wet filling. Raw apples release a great deal of juice as they bake, and without help that juice would soak the dough and turn the strudel soggy. The Viennese solution is Butterbrösel: fine breadcrumbs toasted in plenty of butter until golden. Scattered over the dough beneath the apples, they absorb the juice, bind the filling and add a toasty, buttery flavour.

The choice of apple matters just as much. Austrian cooks favour tart, firm apples that keep some shape but soften readily, such as Boskoop; Bramley, Granny Smith or another sharp variety works well. Sweet dessert apples give a bland, mushy filling. The apples are sliced thinly so they cook through in the time the pastry takes to bake, and mixed with sugar, cinnamon and lemon juice only at the last moment, so they do not start to weep before the strudel goes into the oven.

The dough itself is made from strong flour, water, oil and salt, kneaded to a smooth, elastic ball and rested until it is relaxed enough to stretch over a floured tablecloth until it is translucent. Melted butter brushed over the stretched dough and again over the finished roll is what makes the many thin layers bake into a shattering, flaky crust.

Rolling is done with the cloth: lifting one edge makes the strudel roll itself up loosely around the filling, without the dough being handled. A loose roll matters, because the apples steam and expand in the oven; rolled too tightly, the strudel splits.

iii. Ingredients

Makes 10 servings · scroll the side panel to adjust

• 250 g strong white bread flour
• 130 ml lukewarm water
• 2 tbsp neutral oil, plus extra for brushing
• 1 pinch salt
• 1 kg tart apples (Boskoop, Bramley or Granny Smith)
• 1 lemon, juice and finely grated zest
• 80 g raisins
• 3 tbsp dark rum
• 100 g caster sugar
• 2 tsp ground cinnamon
• 80 g fine dry breadcrumbs
• 60 g unsalted butter, for the breadcrumbs
• 80 g unsalted butter, melted, for brushing
• 40 g chopped walnuts (optional)
• 2 tbsp icing sugar, to dust

Strong bread flour gives the elastic gluten needed for stretching; Austrian cooks use a fine, high-protein flour (Weizenmehl glatt). Tart apples are essential for flavour and texture; peel, core and slice them thinly. The breadcrumbs should be fine and dry, not fresh, and toasted in butter until golden. Rum-soaked raisins are traditional; omit the rum if you prefer and soak them in apple juice. Walnuts are a common addition. Ready-made filo pastry is a reasonable shortcut: use 6–8 sheets, each brushed with butter.

iv. Method

1. Mix the flour, water, oil and salt and knead for 8–10 minutes, until very smooth, silky and elastic. Shape into a ball, brush with oil, cover with a warmed bowl and rest for at least 1 hour. Soak the raisins in the rum.
2. Melt the 60 g butter in a frying pan, add the breadcrumbs and toast over a medium heat, stirring, for 3–4 minutes until golden. Cool.
3. Heat the oven to 190 °C (375 °F), conventional heat. Line a large baking tray with baking paper.
4. Peel, core and thinly slice the apples. Just before assembling, toss them with the lemon juice and zest, sugar, cinnamon, drained raisins and walnuts.
5. Spread a large tablecloth over a table and dust with flour. Roll the dough out a little, then lift it on the backs of your hands and stretch it gently from the centre outwards, working around the table, until it is translucent, about 80 × 60 cm. Trim off the thick edges.
6. Brush the dough with some of the melted butter. Scatter the breadcrumbs over the third of the dough nearest you, leaving a 5 cm border at the sides, and pile the apple mixture over the breadcrumbs.
7. Fold the side edges in over the filling. Lift the tablecloth so the strudel rolls itself up loosely, and roll it onto the baking tray seam side down, curving it into a horseshoe if necessary. Brush generously with melted butter.
8. Bake for 40–45 minutes, brushing with butter once or twice, until deep golden and crisp and the apples are tender when tested with a skewer. Rest for 15 minutes, dust with icing sugar and slice with a serrated knife.

v. Tips & common mistakes

• Mix the filling at the last minute. Sugared apples start to release juice almost immediately. Prepared too early, they flood the pastry.
• Toast the breadcrumbs properly. Pale, untoasted crumbs turn pasty. Golden, buttery crumbs absorb juice and add flavour.
• Choose sour, firm apples. Sweet apples make a bland, sludgy filling. Boskoop, Bramley and Granny Smith hold their character.
• Slice the apples thinly. Thick chunks stay hard while the pastry burns. Slices about 3 mm thick bake through evenly.
• Do not roll too tightly. The filling expands as it bakes. A loose roll stays intact; a tight one bursts.
• Serve on the day. Strudel pastry is at its crispest within a few hours of baking. Reheat leftovers in the oven, never the microwave.

vi. Variations

Austrian cooks make strudel with many fillings. Topfenstrudel uses sweetened quark; Mohnstrudel uses poppy seeds; Weichselstrudel uses sour cherries; Milchrahmstrudel, the oldest recorded type, is baked in a dish with a milk and cream custard. In South Tyrol, apple strudel is often made with a shortcrust dough (Mürbteig) instead of stretched dough, and in Germany a puff pastry version is common. Some Viennese cooks add a spoonful of sour cream to the apples.

Outside Austria, apple strudel is close to the Hungarian almás rétes, and it shares a love of apples and cinnamon with the Polish apple cake szarlotka, the English apple pie and the apple turnover. Layered pastries like Greek galaktoboureko show the filo side of the family.

vii. Serving & storage

Apfelstrudel is served warm, in thick slices dusted with icing sugar. In Vienna it is offered with a choice of Schlagobers (lightly sweetened whipped cream), vanilla sauce or vanilla ice cream, and eaten as an afternoon treat with coffee or as a dessert after a meal.

It is best on the day of baking. Covered at room temperature, it keeps for a day or two; reheat slices in a 180 °C (355 °F) oven for 10 minutes to crisp the pastry again. Baked strudel freezes well for up to two months; reheat from frozen in a moderate oven for 20–25 minutes. You can also freeze the assembled, unbaked strudel on a tray, wrapped, and bake it from frozen, adding 10–15 minutes to the baking time.

ix. More from Austrian & German

• Topfenstrudel — quark strudel
• Poppy Seed Strudel — Mohnstrudel
• Kaiserschmarrn — shredded Austrian pancake
• Linzer Torte — nut-and-jam lattice tart
• Szarlotka — Polish apple cake
• Apple Pie — double-crust fruit pie