Mix 20 grams flour and 100 ml milk in a small saucepan and bring to a boil. Cook shortly until thick; set aside to cool.

In a bowl of stand mixer (or if using your hands for kneading, use large bowl) add milk, yeast and sugar and let it rise for 10 minutes until bubbly. Add in sour cream, 400 grams flour, cinnamom, nutmeg, salt, egg, vanilla and lukewarm slurry and using the dough hook attachment, mix on low speed until your dough comes together. Add in the butter, piece by piece and continue kneading on medium speed for about 10 minutes until the dough is no longer sticky and is elastic. Add in chocolate chips and use lightly floured hands to finish mixing to form soft dough. (If the dough seems very, very soft and sticky, add the rest of the flour, tablespoon by tablespoon, mixing between additions until smooth and stretchy but still soft. Stop adding the flour when you get to that point.) Gather the dough into a ball shape.

Grease a large bowl with oil. Place dough into a greased bowl and cover with plastic wrap. Let it proof until it’s doubled in size, about 1.5- 2 hrs.

Grease 33x23 cm (9x13-inch) baking pan with butter.

Deflate the dough by punching it down and and divide the dough into 15 equal portions, if you want them the same size, weight the dough. Roll each piece into a smooth ball on a lightly floured work surface, pinching it on the bottom to seal. Arrange in prepared baking pan.

Cover with kitchen towel and let it rise for 45 minutes. While buns are rising, preheat oven to 180°C ( 350°F).

For flour crosses, mix flour and water until a thick, but still runny paste forms. Spoon into a piping bag or small ziplock bag (snip off a small piece at the corner).

Pipe a line along each row of buns, then repeat in the other direction to create crosses.

Bake 20-25 minutes or until golden brown.

While buns are baking, make syrup glaze. Heat water and sugar in a small saucepan on high until sugar has dissolved completely. Set aside.

After you take the buns out of the oven, immediately brush tops with prepared syrup. Allow to cool to warm before serving.