Stir, cover tightly with clingfilm and set aside for until the mix is bubbly and frothy, (about 10 minutes)

Combine flour, remaining sugar and salt, in a larger bowl

Grate the frozen butter into the bowl.

Use your fingertips to quickly rub the frozen butter into the flour until most of the flour is incorporated. There will still be bigger pieces of butter. Do not mix the butter in completely. The mix will be the texture of coarse breadcrumbs.

Add the yeast mixture into the flour/butter mixure. Using a silicone spatula or wooden spoon, bring the dough together into a rough mass Do not knead.

Stir gently for a few seconds to moisten to create a thick and sticky dough.

Tip the dough onto a large piece of plastic wrap and pat into a rough square approximately 5" x 5".

Wrap the square tightly and refrigerate for 4 fours.

Unwrap the cold dough and place on a silicone mat or piece of parchment paper and lightly sprinkle with flour.

Using a rolling pin, press down on the dough to lightly flatten it, then roll into an 8x10 inch rectangle. Stretch the corners as need to produce a rectangle.

Take one side edge and fold into the center. Take the other side edge and fold into the center.

Cover dough lightly with the same sheet of clingfilm and slide the mat onto a baking tray. Place in the fridge for about 20 minutes.

Now rotate the mat so that the shorter end of the rectangle is facing you. Repeat the rolling and folding the same way, then chill for another 20 minutes. Then rotate the dough yet again, roll and fold one last time for a total of three folds

Wrap the final rectangle of dough in plastic wrap and place in the refrigerator for about 12 hours. (Or, freeze the dough for future use.)

After 12 hours, it's time to form the cinnamon sticks.

With the soft butter and a bowl with the cinnamon sugar mix close by, unwrap the dough and cut it into two equal parts. Place one half back in the refrigerator and the second on a lightly floured silicone mat.

Cover with plastic wrap and roll into a 6x10 inch rectangle, being as precise as you can.

Spread half the butter all over the dough, and then sprinkle one third of the cinnamon sugar mixture over it in an even layer. Press down lightly with the edge of a knife to help the sugar stick.

Slice the dough into 10 equal strips of 1 inch width. Slide the mat onto a baking tray and refrigerate for 30 minutes.

Repeat this step with the second half of the dough. You will have some of the cinnamon sugar left over for later use.

Preheat the oven to 400 degrees. Line a baking sheet with parchment paper or aluminum foil.

Separate the chilled strips of the dough by gently prying them apart with a sharp knife or metal spatula.

Gently twist each strip to create cinnamon stick shapes. For hearts, shape two 2 of the strips into curves and join at top and bottom. Place sticks on the prepared baking tray, leaving at least a half inch between.

Sprinkle sticks with the remaining cinnamon sugar.

Place the baking sheet in the oven to bake for 20 to 25 minutes until browned on top . Rotate the tray halfway through the baking time for even browning. Do not over cook.

The cinnamon sticks will firm up a few minutes after removal from the oven to make a crispy outer edge and soft insides.

Best eaten warm and fresh, but can be stored at room temperature for 2 to 3 days (they will soften once covered), or refrigerated for a week. Reheat gently in the oven before eating. Happy baking!