Make the Dough: In the bowl of a stand mixer fitted with a dough hook, combine the flour, caster sugar, salt, and yeast. Add the beaten egg and lukewarm milk. Mix on a low speed until a shaggy dough forms. Add the 50g of softened butter and knead on a medium speed for 8-10 minutes, until the dough is smooth, elastic, and pulls away from the sides of the bowl.

First Proof: Shape the dough into a ball, place it in a lightly oiled bowl, cover, and let it rise in a warm place for 1-1.5 hours, or until doubled in size.

Prepare the Butter Block: While the dough is rising, place the 280g of cold butter between two sheets of baking parchment. Using a rolling pin, bash and roll the butter into a flat rectangle, roughly 20cm x 15cm. Keep it wrapped in the parchment and place it in the fridge to stay cold but pliable.

Laminate the Dough (First Turn): Knock the air out of the risen dough and roll it out on a lightly floured surface to a rectangle of about 40cm x 20cm. Place your chilled butter block in the centre of the dough. Fold the two outer thirds of the dough over the butter, like a letter, completely encasing it. Pinch the seams to seal.

First Fold and Chill: Turn the dough parcel 90 degrees. Roll it out again into a long rectangle, about 60cm x 20cm. Fold it into thirds again (a 'letter fold'). Wrap it in cling film and chill in the fridge for 30 minutes. This process, known as lamination, is what creates the flaky layers.

Second Fold and Final Chill: Repeat the rolling and folding process one more time. Wrap the dough again and chill for at least 2 hours, or preferably overnight. This long chill relaxes the gluten and solidifies the butter layers.

Shape the Cruffins: On a lightly floured surface, roll the chilled dough into a large rectangle, about 60cm x 30cm and 3-4mm thick. Brush the entire surface with the 50g of melted butter. In a small bowl, mix the 150g of caster sugar and 2 tsp of cinnamon, then sprinkle this evenly over the buttered dough.

Roll and Cut: Tightly roll the dough up from one of the long edges to form a long log. Trim the ends. Using a sharp knife, cut the log into 12 equal pieces (about 5cm each). Now, this is the key step: cut each of those pieces in half lengthwise, exposing the layers.

Form and Final Proof: Take one of the halved pieces and, with the cut side facing out, roll it up into a spiral shape. Tuck the end underneath. Place it into a hole of a well-greased 12-hole muffin tin. Repeat with the remaining pieces. Cover the tin loosely and let the cruffins proof in a warm place for 45-60 minutes, until they are puffy and have risen just above the rim of the tin.

Bake to Perfection: Preheat your oven to 200°C (180°C fan). Bake the cruffins for 20-25 minutes, until they are deep golden brown and feel light. Let them cool in the tin for 5 minutes before transferring them to a wire rack. While they are still warm, you can roll them in extra cinnamon sugar for a final flourish.