Henry's Sourdough Japanese Milk Bread (Shokupan)

Ingredients

Sweet Levain (build night before)

• 35g (¼ cup) bread flour
• 35g (2 tablespoons + 1 teaspoon) water
• 7g (1½ teaspoons) granulated sugar — Feeds yeast and reduces sourness
• 15g (1 tablespoon) active sourdough starter — 100% hydration, peaked

Tangzhong

• 30g (¼ cup) bread flour
• 120g (½ cup) whole milk

Main Dough

• 240g (2 cups) bread flour
• 80g (⅓ cup) whole milk — Warmed to 100°F (38°C)
• 50g (1 large) (1 large) large egg — Beaten
• 50g (3½ tablespoons) unsalted butter — Softened
• 15g (1 tablespoon + 1 teaspoon) granulated sugar
• 6g (1 teaspoon) fine sea salt
• All (All) ripe sweet levain
• All (All) cooled tangzhong

For the Top

• 15g (1 tbsp) milk or egg wash — Milk for brushing, or 1 egg beaten with 1 tbsp milk

Total flour: 305

Hydration: 65.5

Equipment

Method

Build the Sweet Levain (9:00 PM, night before)

The sweet levain is the key to this recipe. Adding sugar feeds the yeast, speeds fermentation, and results in a sweeter, less sour flavor profile.

1. In a small jar, combine the flour, water, sugar, and active sourdough starter. Mix well until no dry flour remains.
2. Cover loosely and let ripen overnight at room temperature (70-76°F), about 10-12 hours.
3. The levain is ready when it has doubled, looks bubbly throughout, and smells mildly sweet and tangy. It should dome slightly on top, not collapse.

Make the Tangzhong (8:00 AM)

The tangzhong gelatinizes the starches in the flour, allowing them to hold more moisture for an incredibly soft crumb.

1. In a small saucepan, whisk together the flour and milk until smooth.
2. Cook over medium-low heat, stirring constantly, until the mixture thickens into a paste (like mashed potatoes), about 3-5 minutes. It should reach approximately 150°F (65°C).
3. Spread onto a plate to cool quickly. Press plastic wrap directly on the surface to prevent a skin. Let cool to room temperature before using.

Mix the Dough (9:00 AM)

Building gluten in enriched doughs takes patience. The butter goes in last so it doesn't interfere with gluten development.

1. Cut the butter into ½-inch pieces and set out to soften.
2. In the bowl of a stand mixer fitted with the paddle attachment, combine: bread flour, warm milk, beaten egg, sugar, salt, all of the ripe sweet levain, and all of the cooled tangzhong.
3. Mix on low speed (Stir on a KitchenAid) for 1-2 minutes until everything comes together and no dry flour remains.
4. Switch to the dough hook. Mix on medium speed (setting 2-3) for 4-5 minutes until the dough smooths out and starts clinging to the hook. It will still stick to the bottom of the bowl. That's okay.
5. Let the dough rest in the bowl for 10 minutes.
6. Resume mixing on low speed for 2-3 minutes until the dough gains more strength.
7. With the mixer running on low, add the softened butter one piece at a time. Wait for each piece to mostly incorporate before adding the next. This takes 5-8 minutes total.
8. The finished dough will be very soft and slightly sticky. It won't fully clear the sides of the bowl. That's normal for this enriched dough.
9. Transfer to a lightly greased container for bulk fermentation.

Bulk Fermentation (9:30 AM - 1:30 PM (about 4 hours))

Keep the dough at 74-78°F. If your kitchen is cool, use a proofing box or your oven with just the light on.

1. First set of stretch and fold (30 minutes in): With wet hands, stretch one side of the dough up and fold it over to the opposite side. Rotate the bowl 90° and repeat. Do this 4 times total, going around the bowl. The dough will feel loose and extensible.
2. Second set (1 hour in): Turn the dough out onto a clean counter. Perform a few gentle slap and fold until the dough tightens and smooths. Shape into a ball and return to the container.
3. Let the dough rest undisturbed for the remaining 2½ hours.

Tip: The dough is ready when it has roughly doubled in volume, looks puffy and smooth, small bubbles are visible on the surface and sides, and it feels light and airy when you lift the container.

Final Proof (1:45 PM - 5:15 PM (about 3½ hours))

The longer proof time compared to commercial yeast is normal for sourdough. Watch the dough, not the clock.

1. Cover the pan with a large plastic bag or damp towel.
2. Let the dough rise at room temperature (74-78°F) until it reaches about 1 inch above the rim of the pan.

Tip: The dough should look puffy and pillowy, jiggle gently when you shake the pan, and spring back slowly when poked (leaving a slight indent). At cooler temperatures, this could take 4-5 hours. Don't rush it.

Divide and Shape

This is a soft dough, so handle it gently. The three-ball method creates the signature pull-apart look.

Three-Ball Method

Creates even rising and the classic pull-apart look

1. Grease a 9x5-inch loaf pan (or Pullman pan) with butter or neutral oil
2. Gently turn the dough onto a lightly floured surface
3. Divide into 3 equal pieces (about 200g each)
4. Working with one piece at a time, cup your hands around the dough
5. Drag it toward you on the counter, using the friction to create tension on the surface
6. Rotate slightly and repeat until you have a taut ball
7. Place each ball seam-side down in the pan, fitting them snugly side by side
8. Cover the pan with a large plastic bag or damp towel

Bake the Bread

Preheat oven to 350°F (175°C) with a rack in the lower third, about 20-30 minutes before baking.

Oven: 175°C / 350°F. Internal temperature when done: 88-91°C / 190-195°F.

Mountain Top (Standard Loaf Pan) (recommended)

Produces a golden, domed top perfect for toast

Equipment: 9x5-inch loaf pan,Instant-read thermometer

1. Brush top. Gently brush the top with milk or egg wash.
2. Bake. Bake uncovered for 30-40 minutes until the top is deep golden brown and internal temperature reaches 190-195°F (88-91°C).
3. Tent if needed. If the top browns too quickly, tent with foil for the last 10 minutes.

Square Loaf (Pullman Pan)

Produces perfectly square slices ideal for sandwiches

Equipment: Pullman pan with lid

1. Slide lid on. If using a Pullman pan with a lid, slide the lid on. No egg wash needed.
2. Bake. Bake for 35-45 minutes until internal temperature reaches 190-195°F (88-91°C).
3. Check doneness. The loaf sounds hollow when tapped.

Storage

• Room temperature: 5-7 days wrapped tightly in plastic or in a zip-top bag. This bread stays soft remarkably long thanks to the tangzhong and natural fermentation.
• Refrigerated: Not recommended — refrigeration accelerates staling. Freeze instead for longer storage.
• Frozen: Up to 3 months. Slice first, separate with parchment, freeze in a bag. Toast directly from frozen.
• Refresh: Toast slices or warm whole loaf at 350°F (175°C) for 10 minutes

Frequently Asked Questions

Bread tastes too sour. What went wrong?

The levain likely over-ripened. Use it when it's domed and bubbly, before it collapses. Also, bulk fermentation may have gone too long—at warmer temps, it may only need 3-3½ hours. Try a cooler overnight proof for the levain (65-70°F).

Dough didn't rise enough during bulk fermentation. Why?

Your sourdough starter wasn't active enough. Make sure it doubles within 4-6 hours of feeding before building the levain. Also check that your kitchen temperature is 74-78°F.

Bread is dense. How do I fix this?

The dough was likely under-fermented. Extend bulk fermentation until dough has clearly doubled and looks bubbly. Also ensure dough was kneaded enough—it should be smooth and pass the windowpane test.

Crumb is gummy. What happened?

The bread was underbaked—internal temp should hit 195-200°F. Also, you may have cut it too soon. Wait at least 1-2 hours for the crumb to fully set.

Sides collapsed after baking. How do I prevent this?

The dough was overproofed. Bake when dough is 1 inch above the pan rim, not higher. Also try returning the unmolded loaf to the oven for 5 minutes to set the crust.

Can I do an overnight cold proof instead?

Yes! Complete bulk fermentation and shaping as directed. After placing shaped dough in the pan, cover tightly and refrigerate overnight (8-14 hours). Next morning, let warm at room temperature for 1-2 hours until dough rises to 1 inch above pan rim, then bake. Note: This produces a slightly more complex, tangier flavor.

Nutrition

Per serving (1 slice (about 65g)): 195 calories, 32g carbohydrates, 6g protein, 5g fat, 1g fiber, 190mg sodium.