Sourdough Shokupan: Japanese Milk Bread with a Sourdough Twist

Short answer: combine the tangzhong (Japanese flour-water roux) technique with sourdough leavening to create soft, pillowy shokupan with a slight tang. Use milk for richness; bake in a Pullman pan for the iconic square shape.

What shokupan is

Shokupan (食パン) is the standard Japanese sandwich bread:

• Pillowy soft texture
• Slightly sweet
• Even, fine crumb
• Often baked in a Pullman pan (square shape)
• Stays soft for days

The traditional version uses commercial yeast. This sourdough version takes longer but adds flavor.

The tangzhong method

Tangzhong is a flour-water roux:

• Cook 25g flour + 125g milk to a paste
• Cool
• Add to dough

This pre-gelatinizes the starches, increasing water retention. The result is softer, longer-keeping bread.

The recipe

For one 9x5 Pullman pan (or standard 9x5 loaf pan):

For tangzhong:

• 25g bread flour
• 75g milk
• 50g water

For dough:

• 475g bread flour (high protein)
• 50g sugar
• 8g salt
• 75g milk
• Tangzhong (above, cooled)
• 100g active starter
• 1 large egg
• 50g butter, softened

Method

Make tangzhong

In a small saucepan, whisk flour, milk, water. Cook over medium-low, whisking constantly, until thick paste forms (about 3 min, 150°F internal).

Cool fully.

Mix dough

Combine flour, sugar, salt in mixer bowl.

Add milk, tangzhong, starter, egg. Mix to shaggy.

Add softened butter in pieces. Knead 8–10 min until smooth and elastic.

Bulk

Bulk 4–6 hours at 75°F until dough rises 50–60%.

Shape

Divide dough into 3 equal pieces.

For each:

• Roll into a rectangle
• Fold like a letter
• Roll into a tight log

Place 3 logs in a greased Pullman pan.

Final proof

2.5–3 hours at 75°F until dough rises to 1cm below the pan rim.

Bake

Preheat to 350°F (lower than usual).

For Pullman pan: cover with lid (creates the iconic square shape).

Bake 35–40 min, internal temp 200°F.

Remove from pan immediately. Cool fully on rack.

Why a stand mixer

Shokupan dough is enriched (butter, egg) and needs significant kneading. By hand:

• 15+ minutes
• Wears out arms
• Hard to develop properly

A stand mixer:

• 8–10 min
• Consistent gluten development
• Less effort

Worth it for shokupan.

Why a Pullman pan

A Pullman pan with lid:

• Creates the iconic square shape
• Confines the dough during the bake
• Produces a soft, even crust
• Slices clean for sandwiches

If you don't have one, a 9x5 standard pan works (just don't cover).

Variations

Honey shokupan

Replace sugar with 60g honey. Slightly different tenderness.

Milk-only shokupan

Replace water in tangzhong with more milk. Richer.

Black sesame shokupan

Add 30g toasted black sesame seeds + 1 tbsp sesame oil.

Matcha shokupan

Add 2 tbsp matcha powder. Bright green color.

Chocolate shokupan

Add 50g cocoa + 80g chocolate chips.

Cheese shokupan

Add 80g cubed cheese in the shape (one piece per log).

Storage

Shokupan keeps amazingly well:

• Counter, cloth bag: 4–5 days (still soft!)
• Refrigerated: don't (gets stale)
• Frozen, sliced: 3 months

The tangzhong preserves moisture.

What to make

Shokupan is for:

• Sandwiches (cleanest cut, ideal shape)
• Toast (buttery, perfect)
• French toast (custard-soaking quality)
• Tea sandwiches (cucumber, egg salad)
• Strawberry shortcake bread

It's the most versatile sandwich bread.

A perfect Japanese sandwich

Shokupan tonkatsu sandwich:

• Toasted thick slices
• Mayo
• Sliced cabbage
• Crispy fried pork cutlet
• Tonkatsu sauce

This is the pinnacle of sandwich-as-art.

A breakfast use

Toast thick slices. Top with:

• Butter and salt (the simplest, the best)
• Or egg salad
• Or strawberry jam and butter

Shokupan toast is its own genre.

Why sourdough shokupan

Most shokupan uses commercial yeast for speed. Sourdough adds:

• Slight tang (a counterpoint to the sweetness)
• Better keeping
• More complex flavor
• Longer fermentation depth

The trade-off is time (8+ hours total vs 4 with yeast).

A weekend project

Saturday morning: make tangzhong, mix dough Saturday afternoon: bulk, shape Saturday evening: refrigerate (cold retard for flavor) Sunday morning: pull, proof, bake

Fresh shokupan by Sunday lunch.

Cost analysis

Shokupan ingredients:

• Bread flour: $1
• Milk, butter, egg: $1.50
• Other: $0.50
• Total: $3 per loaf

Bakery shokupan (in Asian markets): $5–8.

Significant savings, equal quality.

Why this is hard but worth it

Shokupan is more technical than country sourdough:

• Tangzhong adds a step
• Enriched dough needs mixer
• Long final proof
• Specific shape

But the result:

• Superior texture
• Stays soft for days
• The best toast bread you've made

Worth the effort.

A tea sandwich use

For an afternoon tea:

• Crustless slices
• Butter and cucumber
• Or egg salad
• Or smoked salmon and cream cheese

Shokupan is the classic English tea bread + Japanese precision.

A final note

Once you've made shokupan once, you'll understand why it's beloved.

The texture is unlike any other bread. The keeping is exceptional. The versatility is unmatched.

Bake one for a special occasion. Then bake one regularly. It quietly becomes a favorite.