Step 1: In a small bowl, warm the milk to about 105-115°F (40-46°C). Sprinkle in the active dry yeast and a pinch of granulated sugar. Stir gently and let it sit for 5-10 minutes until foamy. This proves your yeast is active. If it doesn't foam, your yeast might be dead, and you should start again with fresh yeast.
Step 2: In a large mixing bowl (or the bowl of a stand mixer fitted with the dough hook), combine the remaining granulated sugar, melted butter, buttermilk, egg, vanilla extract, and salt. Add the foamy yeast mixture and mix well.
Step 3: Gradually add the all-purpose flour and Dutch-processed cocoa powder, mixing until a shaggy dough forms. Add the red gel food coloring, a little at a time, until you achieve a vibrant red color. You want a deep, rich hue for your Red Velvet Cinnamon Rolls.
Step 4: Knead the dough for 5-7 minutes until it's smooth, elastic, and no longer sticky. If using a stand mixer, let it do the work. If kneading by hand, dust your surface lightly with flour as needed, but try not to add too much extra flour.
Step 5: Lightly grease a clean bowl with oil. Place the dough in the bowl, turning once to coat. Cover the bowl with plastic wrap or a clean kitchen towel and let it rise in a warm place for 1 to 1.5 hours, or until doubled in size. A warm oven (turned off, with the light on) works perfectly.
Step 6: While the dough is rising, prepare the filling. In a medium bowl, combine the softened unsalted butter, light brown sugar, Dutch-processed cocoa powder, and ground cinnamon. Mix until well combined and paste-like.
Step 7: Once the dough has doubled, gently punch it down to release the air. Turn it out onto a lightly floured surface. Roll the dough into a large rectangle, approximately 18x12 inches (45x30 cm). Aim for an even thickness.
Step 8: Spread the prepared filling evenly over the entire surface of the dough, leaving about a 1/2-inch border on one of the long edges. This will help seal your Red Velvet Cinnamon Rolls.
Step 9: Starting from the long edge opposite the border, carefully roll the dough tightly into a log. Pinch the seam closed to secure it.
Step 10: Using a sharp, un-serrated knife or dental floss, slice the log into 12-14 equal-sized rolls, about 1 to 1.5 inches thick. For neat cuts, slide dental floss under the log, cross the ends over the top, and pull to cut. This method keeps the Red Velvet Cinnamon Rolls perfectly round.
Step 11: Lightly grease a 9x13 inch baking dish. Arrange the sliced Red Velvet Cinnamon Rolls in the prepared dish, leaving a little space between each roll. They will expand as they rise and bake.
Step 12: Cover the baking dish with plastic wrap or a clean towel and let the rolls rise again in a warm place for another 30-45 minutes, or until visibly puffy.
Step 13: Preheat your oven to 375°F (190°C). Bake the Red Velvet Cinnamon Rolls for 20-25 minutes, or until the edges are lightly golden and the centers are cooked through. If they start to brown too quickly, you can loosely tent them with foil.
Step 14: While the rolls are baking, prepare the cream cheese frosting. In a medium bowl, beat the softened cream cheese and unsalted butter together until smooth and creamy. Add the powdered sugar, vanilla extract, and a pinch of salt. Beat until light, fluffy, and lump-free. Add a splash of milk if needed to reach desired consistency.
Step 15: Once the Red Velvet Cinnamon Rolls are out of the oven, let them cool in the pan for about 5-10 minutes. This allows them to set slightly. Then, generously spread the cream cheese frosting over the warm rolls. The warmth will slightly melt the frosting, allowing it to seep into every delicious crevice. These are best served warm, but are also delicious at room temperature!