Jam-Filled Hokkaido Milk Rolls

Directions

1. In a small microwave-safe bowl, whisk 3 tablespoons bread flour with 1/2 cup water. Microwave the mixture for 40-80 seconds, or until it has a pudding-like texture, stopping every 20 seconds to whisk and check the texture.
2. In a large bowl or the bowl of a stand mixer, whisk together the paste (from step 1), milk and egg until fully combined. Add the yeast and remaining flour and stir or mix on low until no dry flour remains. Cover the bowl and let the dough rest for 15 minutes.
3. Add the sugar and salt. Then knead the dough, by hand or on low speed, for 5 minutes. Continue kneading as you add 3 tablespoons of softened butter to the mixture one tablespoon at a time. Once the butter is fully incorporated, turn the mixer to medium-low or continue kneading by hand. Knead until the dough is smooth springy, about 10 minutes by hand or 5 minutes in the mixer.
4. Form the dough into a smooth, round ball and place it seam-side down in a lightly greased bowl. Cover with a damp tea towel, bees wrap or a silicone bowl cover and let rest for 1 to 1 1/2 hours, or until doubled in size. Toward the end of the dough's rise time, preheat the oven to 350 F.
5. After the dough has risen, grease a 10-inch oven-proof skillet. Press down on the dough to deflate any large air bubbles and turn it out onto a lightly floured surface. Press and roll the dough into a 16-inch by 12-inch rectangle with the long side parallel to the counter.
6. Gently spread the jam over the dough, leaving a 1-inch border around the perimeter of the dough. Starting with one of the long sides, roll the dough into a cylinder. Trim the ends, then cut into 6 even rolls. Transfer the rolls to the greased skillet and cover them loosely. Let the rolls rise for 30 minutes to 1 hour, or until they've filled out the skillet. Bake rolls for 30-40 minutes, or until golden brown. Brush with melted butter and serve warm!