Jam and Margarine Koppepan (ジャムマーガリンコッペパン)

Ingredients

Equipment Needed

• •Kitchen scale
• •Bench scraper
• •Baking sheet
• •Parchment paper
• •Serrated knife

Instructions

1. 1

   Mix the dough

   In a large bowl, whisk the flour, sugar, salt, and yeast. Add the lukewarm milk and beaten egg, then mix until no dry flour remains. The milk should feel warm, not hot, because yeast works steadily in gentle warmth and sulks when scalded.

2. 2

   Knead until smooth

   Knead for 8 to 10 minutes, then work in the softened butter a little at a time. At first the dough will smear and complain. Keep going. The butter coats the flour after gluten has begun to form, giving you a soft crumb without making the dough weak from the start.

   The dough is ready when it feels elastic, slightly tacky, and can stretch into a thin sheet before tearing.
3. 3

   First rise

   Set the dough in a lightly oiled bowl, cover it, and let it rise in a warm place until doubled, about 60 to 75 minutes. Don't chase the clock. A well-risen dough looks swollen and relaxed, and a floured finger pressed into it leaves a slow, shallow dent.

4. 4

   Divide and rest

   Turn the dough out and divide it into 8 equal pieces, about 70g each. Shape each piece into a loose ball, cover, and rest for 15 minutes. This pause lets the tightened gluten relax, so the rolls shape neatly instead of springing back like a child told to sit still.

5. 5

   Shape the koppepan

   Flatten each piece into an oval, fold the long edges toward the center, then roll it into a smooth spindle about 14cm long, tapering the ends slightly. Pinch the seam closed and place seam-side down. The shape matters because koppepan should be long enough to split cleanly and soft enough to cradle the filling without cracking.

6. 6

   Proof the rolls

   Place the rolls on a lined baking sheet with space between them. Cover and proof until puffy and light, 35 to 45 minutes. If underproofed, they bake dense and split at the sides. If ready, a gentle touch leaves a small mark that slowly fills back in.

7. 7

   Bake pale gold

   Bake at 180 C for 13 to 15 minutes, until pale golden on top and lightly browned underneath. Koppepan is not a crusty bread. Pull it before the crust toughens, because the pleasure here is the soft bite against the cool jam and margarine.

8. 8

   Cool completely

   Move the rolls to a rack and cool completely. Warm bread melts the margarine and loosens the jam, which sounds harmless until the filling runs out the bottom and the bread turns greasy. Patience is doing real work here.

9. 9

   Split and fill

   Cut each roll lengthwise from the top, stopping just before you cut through the bottom. Spread jam along one inner side and margarine along the other, then close the roll gently. Keep the two fillings separate. That clean meeting in the middle is the Yamazaki way, and it is the detail that decides the bread.

Chef Tips

• •Use margarine for this one if you're chasing the real taste. Butter is not a scandal, but it makes the filling richer and more fragrant, which moves the bread away from the convenience-store classic.
• •Don't brown the rolls too deeply. Koppepan should stay soft and pale, with only a gentle color on the crust. A hard crust fights the filling.
• •Fill only after the bread is fully cool. Warm bread makes the margarine slide and the jam soak in too quickly, and then the clean two-sided filling disappears.

Advance Preparation

• •The rolls can be baked one day ahead and kept tightly wrapped at room temperature. Fill them the day you serve them so the crumb stays soft.
• •For longer storage, freeze the unfilled baked rolls for up to one month. Thaw wrapped at room temperature, then split and fill once fully soft.

Frequently Asked Questions

Nutrition Information

1 serving (about 95g)