In a large mixing bowl, combine the flour, granulated sugar, salt, and instant yeast. Stir them together well for an even blend of dry ingredients.
Gradually pour in the warm milk, mixing until a soft dough forms. Knead briefly for about 2-3 minutes until smooth and elastic.
Shape the dough into a rectangle, wrap it in plastic wrap, and refrigerate for at least 30 minutes to firm up the gluten.
Place the cold unsalted butter between two sheets of parchment paper. Pound and roll the butter into a rectangle about 1/2 inch thick, then refrigerate until firm.
On a lightly floured surface, roll the chilled dough into a rectangle about 1/4 inch thick, ensuring even thickness for optimal flakiness.
Place the chilled butter block in the center of the dough rectangle. Fold the dough over the butter, sealing the edges completely to encase it snugly.
Roll the dough out into a long rectangle, then fold it into thirds like a letter. This is your first turn! Wrap in plastic wrap and refrigerate for 30 minutes to rest.
Repeat the rolling and folding process two more times, chilling the dough for 30 minutes between each turn for that perfect layering.
After the final chilling, roll the dough into a large rectangle again and cut it into triangles about 5 inches wide at the base.
Place a few chocolate chips or a chocolate baton at the wide end of each triangle. Roll them from the wide end to the tip, creating a lovely crescent shape.
Arrange the shaped croissants on a baking sheet lined with parchment paper. Cover loosely with plastic wrap and let them rise in a warm place for about 1–1.5 hours, until doubled in size.
As the croissants rise, preheat your oven to 400°F (200°C) to get it nice and hot for baking.
Beat the egg and brush it delicately over the tops of the risen croissants for that gorgeous golden finish when baking.
Bake the croissants in that preheated oven for 20–25 minutes, or until they’re golden brown and flaky.
Allow the croissants to cool on a wire rack for a few moments before serving.
Enjoy your delicious homemade Chocolate Croissants while they’re warm for the best experience!