• Add the yeast and sugar to a large mixing bowl. In a small saucepan, warm the milk (not the condensed milk) to around 95-104°F / 35-40°C and pour this over the yeast and sugar. If using active dry yeast, let this sit for around 5-10 minutes until it becomes foamy. If using instant yeast this step can be skipped.
• Add in the flour, salt, and condensed milk. Use a wooden spoon until it forms a shaggy dough ball. Once it forms a dough ball, pull it onto a floured surface and knead in the butter, a few cubes at a time.
• Knead by hand for around 10 minutes until the dough is smooth and strong. If you need a break, take it. The dough responds well to resting time. Alternatively, use a stand mixer to knead the dough.
• Once kneaded, form the dough into a dough ball. Transfer the dough to a lightly greased medium bowl and cover. Let the dough rise in a warm place until doubled in size, around about 1 hour. The exact proofing time will depend on your room temperature.

Shaping

• In a small bowl, mix together the brown sugar and ground cinnamon for the filling. Set aside.
• Punch the risen dough down, then pull it from the bowl onto a lightly floured work surface.
• For 6 large rolls - Roll the dough out into a rectangle that measures around 8x9 inches (15cmx25cm). Spread the surface of the dough with softened butter, then spread over the cinnamon-sugar mixture. Roll the dough up from the long end to make a 9-inch/25cm long log. Cut 6 slices measuring around 1.5 inches each.
• For 9 medium rolls - Roll the dough out into a rectangle that measures 8x9 inches (15cmx25cm) - Spread the surface of the dough with softened butter, then spread over the cinnamon mixture. Roll it up to make a 9-inch/25cm long log. Cut 9 slices measuring around 1 inch each.
• For 12 mini rolls - Roll the dough out into a rectangle that measures around 7x12 inches (17cmx30cm). Spread the surface of the dough with softened butter, then spread over the cinnamon-sugar mixture. Roll the dough up from the long end into a 12-inch log. Cut 12 equal pieces measuring around 1 inch each.
• Grease a baking tray with butter or line with parchment paper and place in the cut cinnamon rolls. Let them rise at room temperature until doubled in size.
• Preheat the oven to 350°F (180°C) regular oven. Bake the cinnamon rolls in the preheated oven for around 22-25 minutes until golden brown on top. If they are browning too fast, you can cover the top of the dough with aluminum foil.

Frosting

• Using a hand-held mixer or some arm muscle, beat the cream cheese until it's smooth. Add in powdered sugar, vanilla, and milk. Beat it together until creamy. Spread the icing over the still-warm cinnamon rolls and serve the warm rolls immediately.