In a large bowl, combine warm milk, sugar, and yeast. Let it sit for 5–10 minutes until foamy. Stir in butter, eggs, and salt, then gradually add flour to form a soft dough. Knead for 8–10 minutes until smooth and elastic.
First Rise:
Place the dough in a greased bowl, cover, and let rise in a warm place until doubled in size, about 1–2 hours.
Shape the Rolls:
Roll the dough into a rectangle on a floured surface. Spread softened butter over the surface, sprinkle with sugar and blueberries, and add lemon zest if using. Roll the dough tightly into a log and cut into equal slices.
Second Rise:
Place the rolls in a greased baking pan, cover, and let rise for 30–45 minutes until puffy.
Bake:
Preheat oven to 375°F (190°C). Bake rolls for 20–25 minutes, until golden brown.
Glaze:
While rolls are warm, whisk together powdered sugar and milk or lemon juice to make a smooth glaze. Drizzle over the rolls.
Serving and Storage Tips
