Combine warm milk, water, sugar, and yeast in a bowl. Let sit until foamy (about 5-10 minutes).

Add flour, salt, and egg. Mix until a soft dough forms.

Knead the dough for 5-8 minutes until smooth.

Cover and let the dough rise until doubled in size (about 1 hour).

Roll out the dough into a rectangle.

Place cold butter evenly over ⅔ of the dough.

Fold into thirds like a letter. Rotate, roll, and repeat 3 times, chilling in between folds.

Roll the dough into a large rectangle.

Spread your chosen filling (e.g., cinnamon sugar or Nutella).

Roll tightly into a log, then slice it lengthwise.

Coil each piece into a spiral and place them into greased muffin tins.

Let the cruffins rise for 30–45 minutes until puffy.

Bake at 375°F (190°C) for 20–25 minutes or until golden brown.

While still warm, roll the cruffins in cinnamon sugar or dust with powdered sugar.

Optional: Drizzle with caramel or melted chocolate for extra decadence.