Stir the warm whole milk, active dry yeast, and a small portion of the granulated sugar together. Let the mixture stand for about 5 minutes, until foamy.

Mix in the remaining sugar, butter, eggs, and salt. Add the flour gradually until a soft, slightly tacky dough forms.

Knead the dough by hand for 5–8 minutes or with a dough hook for 4–5 minutes, until smooth. Place it in a lightly greased bowl, cover, and let it rise in a warm, draft-free place for about 1 hour, or until doubled.

Roll the risen dough into an approximately 12 x 18-inch rectangle. Spread it with the softened filling butter, then sprinkle evenly with the brown sugar and cinnamon before rolling tightly from the long side.

Cut the log into 12 even pieces and arrange them in a greased 9 x 13-inch baking dish. Cover and let rise for 20–30 minutes, until puffy.

Bake at 350°F for 20–25 minutes, until lightly golden and cooked through in the center. Avoid overbaking because the rolls continue to firm as they cool.

Beat the frosting butter and cream cheese together until smooth. Add the powdered sugar, vanilla, and salt, beat again, and spread the frosting over the warm, slightly cooled rolls.