Combine the warm milk and active dry yeast in a small bowl. Allow it to sit for 5–10 minutes until it becomes frothy and bubbly.

In a large mixing bowl, whisk together the all-purpose flour, bread flour, granulated sugar, and salt.

Add the melted butter and the frothy yeast mixture into the dry ingredients. Mix everything until a soft dough forms.

Transfer the dough to a floured surface and knead for about 5–7 minutes until it's smooth and elastic. Place into a greased bowl to rise.

Using a food processor, blend the shelled pistachios until finely ground.

Add the powdered sugar, heavy cream, vanilla extract, and almond extract to the blended pistachios. Blend until smooth.

Punch down the risen dough and roll it out into a rectangle about 1/4 inch thick.

Cut the dough into triangles, about 4–5 inches wide at the base.

Place a spoonful of your pistachio cream at the base of each triangle and roll from the base to the tip.

Arrange the shaped croissants on a parchment-lined baking sheet and let them rise for 30–45 minutes.

Preheat your oven to 375°F (190°C).

Beat the egg and brush it over the tops of the croissants.

Bake for 20–25 minutes until golden brown and flaky.

Allow the croissants to cool slightly before serving.