Preheat and Prepare: First, preheat your oven to 190°C (170°C fan). Grease a 12-hole standard muffin tin with a little butter or a light spray of oil.

Prepare the Filling: In a small bowl, mix together the 50g of light brown soft sugar, 2 teaspoons of ground cinnamon, and the pinch of nutmeg if you're using it. Set this aside.

Roll Out the Pastry: Unroll your chilled puff pastry sheet onto a lightly floured work surface with the long edge facing you. If it's not pre-rolled, roll it into a rectangle approximately 35cm x 25cm.

Add the Filling: Brush about 50g of the melted butter evenly over the surface of the pastry, leaving a small 1cm border along the top long edge. Sprinkle the brown sugar and cinnamon mixture evenly over the butter.

Roll and Cut: Starting from the long edge nearest you, roll the pastry up into a tight log. Press the seam gently to seal. Trim the ends for a neat finish, then slice the log into 12 equal-sized pieces, each about 2.5-3cm thick.

Arrange in Muffin Tin: Place each spiral of pastry into a hole in your prepared muffin tin, with the cut-side facing up so you can see the swirl. I find that gently pressing them down ensures they bake evenly.

Bake Until Golden: Place the tin in the preheated oven and bake for 18-22 minutes, or until the cruffins are puffed up, deeply golden brown, and cooked through. The layers should look distinct and crisp.

Coat the Cruffins: While the cruffins are baking, prepare the topping. In a shallow bowl or dish, mix together the 100g of caster sugar and the remaining 2 teaspoons of cinnamon.

Finish and Serve: As soon as the cruffins come out of the oven, let them cool in the tin for just 2 minutes. Then, carefully remove them. While they are still warm, brush each one all over with the remaining 25g of melted butter, then immediately roll it in the cinnamon-sugar mixture until it's generously coated. Serve them warm.