1-First, start by mixing the ingredients for the dough. Combine 1/4 cup unsalted butter, 4 cups all-purpose flour, 1/4 cup granulated sugar, 2 teaspoons salt, 1 tablespoon active dry or instant yeast, and 1 1/2 cups cold whole milk in a mixer to form a smooth dough, then knead for about 5 minutes. Once done, refrigerate the dough for 30 minutes to let it rest.

2-Next, roll the dough into a 14×10-inch rectangle and chill it for 4 hours or overnight to develop the texture. For the butter layer, blend 1 1/2 cups unsalted butter with 2 tablespoons all-purpose flour, shape it into a 7×10-inch rectangle, and chill for 30 minutes. Emphasize using softened butter here it makes shaping easier and helps avoid lumps.

3-Building the Layers: Now, enclose the chilled butter layer inside the dough and begin laminating. Fold the dough three times, rolling it out and chilling for about 20 minutes between each fold to keep everything cold and prevent butter from leaking. After the final fold, chill the dough for another 4 hours or overnight for the best flakiness. If the dough warms up too much at any point, pop it in the fridge for around 20 minutes to maintain tenderness avoid over-flouring to keep it light.

4-Once chilled, roll the dough into an 8×20-inch rectangle and cut it into triangles. Shape each triangle into a croissant by rolling from the base to the tip and curving the ends, then let them rest for 1 hour at room temperature followed by 1 hour in the refrigerator. Brush with the egg wash made from 1 large egg and 2 tablespoons whole milk, then bake at 400°F (200°C) for about 20 minutes until golden brown.