Instructions

For the Preferment:

1. In a medium bowl, whisk together 60 grams of warm water, yeast, and sugar. Let stand until foamy, 5 to 10 minutes. Stir in the flour until well combined; cover and let stand in a warm, draft-free place until the mixture is puffed and bubbly, 40 minutes to 1 hour. (The mixture will start thick but will loosen as it sits.)

For the Dough:

1. In the bowl of a stand mixer, whisk together warm milk and yeast by hand until combined and dissolved. Add the preferment, 125 grams of flour, room temperature eggs, oil, sugar, honey, salt, lemon zest, and vanilla; using the paddle attachment, mix on low speed until combined, 1 to 2 minutes, stopping to scrape the sides of the bowl. Gradually add 250 grams of flour, mixing until combined.
2. Switch to the dough hook attachment. Mix on low speed until a soft, elastic, slightly sticky dough forms, 7 to 10 minutes, stopping to scrape the sides of the bowl and the dough hook; add up to the remaining 31 grams of flour, 8 grams at a time, if the dough is too sticky. (The dough should pass the windowpane test but may still stick to the bottom and sides of the bowl.)
3. Grease a large bowl with oil. Place the dough in the bowl, turning to grease the top. Cover and let rise in a warm, draft-free place until doubled in size, 1 to 1½ hours.

Preparation:

1. Line 2 baking sheets with parchment paper.
2. On a very lightly floured surface, divide the dough into 10 portions. Gently shape each portion into a ball and pinch any seams to seal. Cover and let stand for 20 minutes.
3. On a lightly floured surface, press or roll each ball into a 10 cm wide disk. Starting with the top edge or one 10 cm long side, fold and roll the dough about 1 cm at a time, gently pressing to seal after each roll. Repeat until you have a cylinder and pinch the seam to seal. Pinch the ends closed; fold in and pinch to secure. Roll the seam to the bottom, and gently roll to form an evenly thick 10 cm long log. Repeat with the remaining dough. Place them seam side down on the prepared pans. Cover and let rise in a warm, draft-free place until nearly doubled in size, 45 minutes to 1 hour.
4. Preheat the oven to 180°C.
5. In a small bowl, whisk together the egg and milk, and brush the tops of the buns with the egg wash.
6. Bake, one batch at a time, until golden brown, 10 to 15 minutes. Let cool completely on wire racks.

For the Vanilla Whipped Cream:

1. In a medium bowl, whip the cream until soft peaks form. Add the sugar and vanilla and whip until stiff peaks form. Use immediately or refrigerate.

Filling:

1. Using a serrated knife held perpendicular to the cutting surface, split the buns lengthwise down the center, stopping just short before cutting all the way through. Fill each bun with caramel cream, lemon curd, and vanilla whipped cream. Using a small offset spatula, let the contours of the bread guide you as you spread, sculpt, and round the cream as needed. Serve immediately.