Combine all the dough ingredients.
Knead for 4 minutes on low speed, then 6 minutes on medium speed.

Cover and let rise for 1 hour at room temperature, then refrigerate for 3 hours.

Shape the butter into a 5 mm (about 1/4 inch) thick square.

Punch down the dough and roll it out so it's as wide as the butter and can fully enclose it.

Roll the dough into a strip, then fold it like a letter.
Fold it over itself again.

Repeat this process once more.

Roll the dough into a square about 1/8 inch (3 mm) thick.

Cut it in half.

For the mini pain au chocolat:

Cut the chocolate sticks and place them on the dough, leaving a finger-width space between each stick.

Roll up the dough around the chocolate.
Place on a baking sheet lined with parchment paper.

For the mini croissants:

Cut triangles from the dough and make a small slit at the base of each triangle.
Gently stretch the base and roll up the croissant from the base to the tip.

Place on a baking sheet lined with parchment paper.

Cover with a kitchen towel and let rise for 1 hour.

Brush with beaten egg and bake for 15 minutes at 350°F (175°C).

Let cool on a wire rack.