In a large bowl, mix together the flour, sugar, and salt.

In a separate bowl, combine the yeast with warm milk and water. Let it sit for roughly 5 minutes until it becomes frothy.

Add the yeast mixture and softened butter to the dry ingredients, stirring until well incorporated. Then, knead the dough on a floured surface for 8 to 10 minutes until it becomes smooth and elastic.

Transfer the dough to a lightly greased bowl, cover it with a clean kitchen towel, and let it rise in a warm area for 1 to 1.5 hours, or until it has doubled in size.

Roll out the dough into a rectangle about 12x18 inches (30x45 cm).

Place the cold, cubed butter evenly over two-thirds of the dough.

Fold the unbuttered third over the center, then fold the remaining third on top, like folding a letter.

Turn the dough 90 degrees, roll it out again, and repeat the folding process twice more. Chill the dough in the fridge for 30 minutes between folds.

Roll the chilled dough into a large rectangle, about 12x18 inches.

Cut the dough into triangles (roughly 4 inches wide at the base).

Starting at the wide base, gently roll each triangle toward the tip to form a crescent shape.

Arrange the shaped Gipfeli on a parchment-lined baking sheet, leaving space between them. Cover lightly with plastic wrap and let them proof for 30–45 minutes until slightly puffy.

Preheat your oven to 375°F (190°C).

Brush the Gipfeli with the egg yolk and milk glaze for a golden finish.

Bake for 15–20 minutes or until golden brown and flaky.