Step 1: Warm the milk (1 cup) to lukewarm (105-115°F or 40-46°C). In a large bowl, dissolve the granulated sugar (1/4 cup) and active dry yeast (2 1/4 teaspoons) in the warm milk. Let it sit for 5-10 minutes until foamy. This indicates the yeast is active.
Step 2: Melt the butter (1/2 cup, unsalted) and let it cool slightly. In a separate bowl, whisk together the melted butter, large egg (1), and egg yolk (1). Add this mixture to the foamy yeast mixture.
Step 3: Gradually add the all-purpose flour (4 1/2 to 5 cups) and salt (1 teaspoon) to the wet ingredients. Mix with a wooden spoon or stand mixer with a dough hook attachment until a shaggy dough forms.
Step 4: Turn the dough out onto a lightly floured surface. Knead for 5-7 minutes, or until the dough is smooth and elastic. It should be soft but not overly sticky. If using a stand mixer, knead on medium speed for 5 minutes.
Step 5: Lightly grease a large bowl with vegetable oil or cooking spray. Place the dough in the bowl, turning it once to coat. Cover the bowl with plastic wrap or a clean kitchen towel.
Step 6: Let the dough rise in a warm place for 1 to 1 1/2 hours, or until doubled in size. A slightly warm oven (turned off) or a sunny spot works well.
Step 7: While the dough is rising, prepare the filling. In a medium bowl, combine the softened unsalted butter (1/2 cup), light brown sugar (1 cup, packed), ground cinnamon (2 tablespoons), and a pinch of salt (1/4 teaspoon). Mix until well combined and smooth.
Step 8: Once the dough has doubled, gently punch it down to release the air. Turn the dough out onto a lightly floured surface.
Step 9: Roll the dough into a large rectangle, approximately 12x18 inches and about 1/4 inch thick. Try to keep the edges as straight as possible.
Step 10: Evenly spread the cinnamon filling over the entire surface of the dough, leaving a small 1/2-inch border clean on one of the long edges.
Step 11: Starting from the long edge opposite the clean border, tightly roll the dough into a log. A tight roll is key to perfectly formed spirals.
Step 12: Use a sharp, un-serrated knife or dental floss to cut the log into 12-15 even slices, each about 1 to 1 1/2 inches thick. For clean cuts, slide dental floss underneath the log, cross the ends over the top, and pull to slice.
Step 13: Lightly grease a 9x13 inch baking dish. Arrange the sliced rolls in the prepared dish, leaving a little space between each roll to allow for a second rise.
Step 14: 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 they look puffy and have nearly doubled in size.
Step 15: Preheat your oven to 375°F (190°C).
Step 16: Bake the cinnamon rolls for 20-25 minutes, or until golden brown on top and cooked through. If they start browning too quickly, lightly tent them with foil.
Step 17: While the rolls are baking, prepare the cream cheese frosting.
Step 18: In a medium bowl, combine the softened cream cheese (4 ounces), softened unsalted butter (1/4 cup), powdered sugar (2 cups), vanilla extract (1 teaspoon), and a pinch of salt (1/8 teaspoon).
Step 19: Beat with an electric mixer on medium-high speed until smooth and creamy. If the frosting is too thick, add a tiny splash of milk or cream (1-2 teaspoons) until it reaches a spreadable consistency.
Step 20: Once the rolls are out of the oven, let them cool for about 5-10 minutes in the pan. Then, generously spread the cream cheese frosting over the warm rolls. Serve warm and enjoy!