Preheat oven to 300F/150C and line a good-sized baking sheet.

If including marzipan, mix together the almond meal, confectioners sugar and egg white and bring it together in a ball. Knead slightly and form into a short log, around 1in/2.5cm thick.

For the stollen itself, first chop the dried plums into small pieces, each plum into roughly 4-6 pieces.

Lightly whisk the egg and saffron together in a small bowl.

In a large bowl, mix together the flour, baking powder, sugar, cardamon, nutmeg and lemon zest. Watch with the lemon zest in particular that it is well distributed as it can clump together.

Add the egg mixture, quark, butter, milk, walnuts and chopped dried plums. Then mix until well combined but try not to overmix.

Next, lightly flour a work surface and turn the mixture out. Flatten it out into a circle around 1in/2.5cm thick. Lay the marzipan log in the middle, if using, and fold one side over the top. If not using marzipan, still fold the dough over to the other side, stopping a bit short of the edge. Gently use the back of your fingers to seal the top and bottom layers - it should end up slightly domed rather than very thick to the edge.

Place on a lined baking sheet with plenty of room for it to spread and bake for 60-70 min until gently golden around the outside and a skewer comes out clean. If you have used marzipan, then don't test in the middle but a bit to the side as the marzipan will probably make it tricky to tell.

Allow to cool on a baking rack.

Once cool, brush the outside with melted butter to give it a light coating then sprinkle with confectioners sugar by rubbing it through a sieve to ensure nice and fine. Serve in slices.