1. Make the dough: In a large bowl, whisk warm milk, yeast, and 1 tablespoon sugar. Let sit 5 to 10 minutes until foamy.

2. Add remaining sugar, eggs, melted butter, vanilla, and 3 1/2 cups flour plus salt. Mix until a shaggy dough forms.

3. Knead in the bowl or with a mixer, adding just enough extra flour to make a soft, slightly tacky dough. Knead 8 to 10 minutes until smooth and elastic.

4. Place dough in a lightly greased bowl, cover, and let rise in a warm spot until doubled in size, about 1 to 1 1/2 hours.

5. Make the blueberry filling: In a small saucepan, combine blueberries, sugar, lemon juice, and a pinch of salt. Cook over medium heat until berries burst and release juices.

6. Whisk cornstarch with 1 tablespoon water, stir into the pan, and simmer until thick and jammy. Cool completely.

7. Make the cinnamon sugar: In a small bowl, stir together brown sugar and cinnamon.

8. Shape the rolls: Turn risen dough onto a floured surface and roll into a 12×18 inch rectangle.

9. Spread softened butter over the dough. Sprinkle evenly with the cinnamon sugar.

10. Dollop and gently spread the cooled blueberry filling over the cinnamon layer, leaving a small clean border along one long edge.

11. Starting from the opposite long side, roll the dough into a tight log and pinch the seam to seal.

12. Slice into 10 to 12 even rolls and arrange in a greased 9×13 inch baking dish.

13. Cover the pan and let rolls rise until puffy and touching, 30 to 45 minutes.

14. Bake at 350°F (175°C) for 22 to 28 minutes, until the tops are lightly golden and the centers are just set. Tent with foil if browning too quickly.

15. Make the frosting: Beat cream cheese and butter until smooth. Mix in powdered sugar, vanilla, and enough milk or cream to reach a spreadable consistency.

16. Spread frosting over warm rolls and serve while soft and gooey.