Mix the quark with the milk, eggs, oil, sugar and lemon zest.
Stir in half the flour.
Mix the rest of the flour with the baking powder and knead into the dough.
The dough should be smooth and firm, not sticky (use a little more or less milk if necessary).
Let rise for about 45 minutes.
Heat the oven to 180C (160C fan), gas 5.
Knead the dough thoroughly again and roll out on a well-floured surface to a square of approx. 35x35 cm
For the filling
Mix the almonds, sugar, egg white and milk to a paste.
Spread the paste on the dough and roll up the dough.
Place on a cookie sheet lined with baking parchment and brush with egg yolk.
Cut 1 cm/1/2 deep zigzags into the loaf and let rise for a further 15 minutes.
Bake for approx. 45 minutes until golden brown.
Allow to cool and serve in slices.