In a separate small bowl, combine 2 tablespoons sugar, milk, and yeast.
Cover the bowl with a dishcloth and leave in a warm place for 10 minutes.
In the bowl of a stand mixer fitted with the whisk attachment, whip together the egg yolk and the melted butter.
Switch to the dough hook attachment.
Add the yeast mixture, the flour, and the salt.
knead for 3 minutes.
Pat the dough into a ball, place it in a lightly greased bowl, re-cover with the dish towel, stow in a warm place, and let rise for 1 hour. The dough should double in size.
Preheat the oven to 375 degrees F. Grease the cylinder molds with shortening.
In a separate bowl, whisk together the cinnamon and sugar. Spread the mixture out on a large baking sheet lined with parchment paper.
On a lightly floured surface, roll the dough to approximately 1⁄8 inch thickness.
Using a small sharp knife, cut 1⁄4 inch thick long strips long or enough to wrap around the cylinder 3 times.
Beat the egg white then brush the strips on both sides with egg white.
Tightly wrap each strip of dough around the molds. Each strip should slightly overlap each other. If you are wrapping more than one dough strip around the mold, leave 1 inch between the pastries.
Brush the wrapped pastries again with egg white. Gently and generously roll them in the cinnamon sugar.
Place the dough wrapped molds on top of a small oven-proof casserole dish or pan. The ends should rest on the edges. The pastry doesn’t touch the bottom or the sides of the dish. I put a baking sheet underneath the casserole dish to make it easier to get it in and out of the oven.
Bake for 18 minutes until they are golden all around.
Remove from oven. Let cool and gently slide the Trdelnik from the molds onto a plate and serve.