Feed your sourdough starter so it's active by morning. Leave the butter needed for the dough on the bench overnight.

Add all the dough ingredients to a large bowl the following morning. Use a fork to mix them together into a sticky and shaggy mound.

Tip the dough onto a clean bench and knead it for around 5-7 minutes until it becomes smooth.

Place the dough in a greased bowl in a warm spot to bulk out by around 50%.

Once bulked out by 50%, cover the bowl and place it in the refrigerator for 2-3 hours to chill and firm up.

Make the butter packet by mixing together the butter and flour into a soft mixture.

Roll the butter mixture out between two sheets of baking paper into a rectangle of about 20 x 25cm (8-inch x 10-inch). Place the butter packet in the fridge to cool.

Take the butter out of the fridge 10 minutes before rolling the dough.

Roll the chilled dough into a 25 x 50cm (10-inch x 20-inch) rectangle.

Lay the butter packet on the bottom half of the dough, then fold the top of the dough over it to encase the butter.

Gently roll the dough again into a rectangle of about 25 x 50cm (10-inch x 20-inch).

Fold the dough into three like a pamphlet, then wrap it up and chill for 30 minutes.

After resting, turn the dough 90° and repeat the folding process twice to complete folds.

Wrap the dough up well and chill overnight.

Remove the dough from the fridge and cut it in half.

Roll one half into a 12cm x 21 cm (5-inch x 9-inch) rectangle and cut into 7 x 3cm strips.

Shape two strips to make U shapes and place them in a greased muffin tray.

Repeat with the second dough half.

Proof the cruffins in a warm spot until doubled in size (4-7 hours).

Preheat the oven to 190°C/375°F.

Bake the cruffins for 20-25 minutes until deep golden brown.

Toss the warm cruffins in granulated sugar. Once cooled, pipe in your favorite fillings.

Store in an airtight container at room temperature for up to 3 days or freeze for up to 3 months.