Mix flour and yeast into a stand mixer fitted with a dough hook attachment on medium low speed. Slowly, add in half of the milk. Once combined, add 1 cup (275 grams) BIGA and mix.
Slowly, add in the remaining milk and mix until the dough looks cohesive.
Add granulated sugar; mix until combined.
Add in butter 1 tablespoon (14 grams) at a time. Allow each piece of butter to fully beat in before adding in a new piece. You can use a silicone spatula to flip the dough over periodically to help the dough hook catch and knead the butter. Scrape down the side of the mixer bowl as needed.
Add in fine sea salt; mix until combined.
Bump the mixer speed up to high, and mix until you hear a popping sound and the dough wraps around the dough hook. Flip the dough as needed to ensure all of the ingredients are fully mixed. The dough will be smooth and sticky.
Roll the dough into a tight ball, then place in a mixing bowl. Cover with plastic wrap, and allow to rise in a warm, draft-free place until doubled in size, about 60–90 minutes. Rise time will vary depending on the temperature of your environment.
Generously, dust a work surface with bread flour and roll the dough into a rectangle about ½ inch (1–2 cm) thick. Use a 3 inch (7 cm) circle cookie cutter to cut about 18 rolls from the dough. Place the rolls on a light colored baking sheet lined with parchment paper at least 3 inches (8 cm) apart. Re-roll the dough and continue cutting rolls until no dough remains.
Lightly, dust the top of the rolls with additional bread flour to ensure nothing sticks to the top. Lightly, cover with plastic wrap and proof at room temperature on the counter until doubled in size, about 30–60 minutes. If your environment is very cold, you can place the rolls in a warm, draft-free spot. Be sure the rolls do not overproof and become flat.
Heat oven to 350°F (180°C).
Remove plastic wrap, and bake rolls for 15–20 minutes, rotating halfway through baking, until lightly golden brown.
Place the baking sheet on a cooling rack, and cover with a tea towel. Allow rolls to cool to room temperature.