Sugar is hygroscopic and melts during proofing, creating liquid that seeps out. Cinnamon is hydrophobic, creating barriers between layers. Butter makes layers slippery. Steam builds up with nowhere to go.

Flour in the filling absorbs excess moisture. Egg wash creates protein bonds that fuse layers. Proper rolling technique with controlled tension. Steam vents poked before baking. Complete cooling before slicing.

In the bowl of your stand mixer, combine warm milk (100-110°F / 38-43°C) and instant-yeast. Let sit 5 minutes until slightly foamy.

Whisk in the sugar and egg until combined.

Add bread flour and salt. Using the dough hook, mix on low speed until a shaggy-mass forms, about 2 minutes.

With the mixer running on low, add the softened butter one tablespoon at a time. Once incorporated, increase to medium speed and knead for 8-10 minutes until the dough is smooth, elastic, and pulls away from the sides. It should pass the windowpane-test.

Use an instant-read-thermometer to check the dough. It should be around 75-78°F (24-26°C) for optimal fermentation.

Form the dough into a smooth ball and place in a lightly greased bowl.

Cover with plastic wrap or a damp towel. Let rise at room temperature (70-75°F / 21-24°C) until doubled in size, about 1-1.5 hours.

Press your floured finger about ½ inch into the dough. If the indentation springs back slowly and partially fills in, it's ready. If it springs back immediately, it needs more time. Use the poke-test to verify.

In a small bowl, whisk together the sugar, cinnamon, flour, and salt until evenly combined. The flour is your insurance policy against gaps.

If using raisins, pulse them in a food processor until they're in ¼ inch pieces or smaller. Large raisins create pockets that cause gaps. Fold into the cinnamon mixture.

The mixture should look like rough sand. If you pinch it, it should hold together slightly from the flour.

In another small bowl, whisk together the egg white and water. This is your binding agent—NOT butter. The protein in the egg white will fuse the layers together as they bake.

Gently punch down the risen dough to deflate. Turn it out onto a lightly floured surface. Let it rest 5 minutes so the gluten relaxes (bench-rest).

Using a rolling-pin, roll the dough into a rectangle approximately 9 inches wide by 18 inches long. The width should match your 9x5 inch loaf pan. The dough should be about ¼ inch thick.

Using a pastry-brush, brush the entire surface of the dough with the egg white wash. Leave a ½ inch border along one long edge for sealing. The egg proteins will fuse the layers together as they bake.

Sprinkle the cinnamon-sugar mixture evenly over the egg-washed dough, leaving that ½ inch border. Don't pile it too thick. Use about 90% of your filling.

Position yourself with a short end facing you. Fold the first ½ inch over to start the roll. Then, using your fingertips, roll the dough forward while simultaneously pulling it back toward you with each roll. This backward tension is the secret—it creates a tight spiral without air pockets.

Brush the clean border with more egg wash, then roll the dough onto the seam. Pinch firmly to seal. Use a bench-scraper to pinch the ends closed as well.

The roll should feel bouncy and have some surface tension. It shouldn't feel like a rock (too tight) or a deflated balloon (too loose).

Set the shaped log seam-side down in a greased 9x5 inch loaf-pan.

Cover loosely with plastic wrap or a damp towel. Let rise until the dough crowns about 1 inch above the rim of the pan, approximately 45-60 minutes.

About 20 minutes before you expect the dough to be ready, preheat your oven to 350°F (180°C). Place a rack in the lower third of the oven.

The dough is ready when you gently poke the top and it springs back slowly, leaving a small indent. Use the poke-test to verify readiness.

Just before baking, use a toothpick or thin skewer to poke 3-4 holes straight down through the top of the loaf, going about 1 inch deep. These vents allow trapped steam to escape.

Place the pan on the lower-third rack. Bake at 350°F (180°C) for 35-40 minutes.

The loaf is done when the top is deep golden brown, it sounds hollow when tapped, and internal-temperature reads 190-195°F (88-90°C) in the center. Use an instant-read-thermometer to verify.

Immediately remove the loaf from the pan and place on a wire-cooling-rack. Brush the top with melted butter while still warm for a soft, golden crust.

Let the loaf cool on the wire rack for at least 1 hour before slicing. The internal structure needs to set, and the cinnamon filling needs to firm up.

Cutting while warm will smush the soft interior, pull the swirl apart, create ragged slices, and potentially destabilize the rest of the loaf.

When you do slice, use a sharp serrated bread knife in a gentle sawing motion. Don't press down; let the knife do the work.

Roll dough into 9x18 inch rectangle, about ¼ inch thick

Brush with egg wash, sprinkle cinnamon-sugar evenly, leaving ½ inch border

Roll from short end using the Sleeping Bag Method—pull back while rolling forward

Seal seam with egg wash, pinch ends closed, place seam-side down in greased pan

Follow the same rolling and filling process as the classic log

Roll up the dough into a tight log

Using a sharp knife, slice the log lengthwise almost to one end (leaving about 1 inch connected)

Twist the two halves around each other, keeping cut sides facing up to expose the swirl

Carefully place the twisted loaf in the greased pan

Preheat oven to 350°F (180°C) with rack in lower third

Poke 3-4 steam vents with a toothpick, about 1 inch deep

Place a metal pan on the bottom rack of the oven during preheat. Just before putting your loaf in, pour about 1 cup of hot water into that pan. The steam during the first 10-15 minutes helps the crust set gradually, which reduces the chance of the top cracking and pulling away from the filling. Remove the water pan after 15 minutes.

Bake 35-40 minutes until deep golden brown

Internal temp should read 190-195°F (88-90°C)

Remove from pan immediately, brush with butter, and cool on wire rack

Preheat to 325°F (165°C) for convection

Poke steam vents as with standard method

Place a metal pan on the bottom rack during preheat. Pour about 1 cup of hot water into it just before baking. Remove after 10 minutes. Convection fans dry the oven faster, so the steam window is shorter.

Bake 30-35 minutes, rotating halfway through

Tent with foil if browning too quickly