Step 1: Prepare the Dough

1. In a large mixing bowl, combine flour, sugar, salt, and yeast.
2. Add the softened butter, warm milk, and beaten egg. Mix until the dough comes together.
3. Knead the dough on a lightly floured surface for 8–10 minutes, or until it’s smooth and elastic.
4. Place the dough in a lightly oiled bowl, cover with a damp cloth, and let it rise for 1–1.5 hours, or until doubled in size.

Step 2: Create the Butter Layer

1. Place the cold butter between two sheets of parchment paper.
2. Roll it out into a thin rectangle, about 5 x 8 inches. Chill until firm.

Step 3: Laminate the Dough

1. Roll the risen dough into a large rectangle, about twice the size of the butter layer.
2. Place the butter in the center of the dough and fold the sides over it, encasing the butter completely.
3. Roll the dough out gently, then fold it into thirds like a letter. Chill for 30 minutes.
4. Repeat the rolling and folding process two more times, chilling between each fold.

Step 4: Shape the Croissant Broodjes

1. Roll out the laminated dough into a large rectangle, about 1/4 inch thick.
2. Cut the dough into triangles for classic croissant shapes or rectangles for filled rolls.
3. For filled croissant broodjes, add a small amount of your chosen filling (e.g., cheese, chocolate, or almond paste) before rolling the dough into its final shape.

Step 5: Proof and Bake

1. Place the shaped rolls on a baking sheet lined with parchment paper. Cover lightly and let them proof for 45 minutes.
2. Preheat the oven to 375°F (190°C).
3. Brush the rolls with the egg wash and bake for 15–20 minutes, or until golden brown and flaky.