01 - Combine warm milk, sugar, and yeast in a large mixing bowl. Let sit for 3–5 minutes until mixture becomes bubbly and foamy.
02 - Add sourdough discard, melted butter, egg, and salt to the yeast mixture. Stir until thoroughly combined.
03 - Gradually incorporate flour, one cup at a time, mixing until a soft, slightly tacky dough forms. Stop adding flour when dough reaches proper consistency—you may not need the full amount.
04 - Turn dough onto a lightly floured surface and knead for 7–8 minutes until smooth, elastic, and springs back when pressed.
05 - Place dough in a lightly greased bowl, cover with plastic wrap or a clean towel, and let rise in a warm, draft-free area until doubled in size, approximately 1 to 1.5 hours.
06 - Punch down risen dough and divide into 8 equal portions. Roll each piece into a smooth log approximately 6 inches long, tapering the ends slightly.
07 - Arrange shaped buns on a parchment-lined baking sheet, leaving 2 inches of space between each. Cover and let rise until puffy and visibly expanded, 30–45 minutes.
08 - Preheat oven to 375°F during the final minutes of the second rise.
09 - Brush risen buns with milk and sprinkle with seeds if using. Bake for 18–20 minutes until golden brown on top and cooked through.
10 - Remove from oven and immediately brush with melted butter for a softer crust. Transfer to a wire rack and cool completely before slicing.