Step 1: In a small bowl, combine warm milk, 1 teaspoon granulated sugar, and active dry yeast. Stir gently and let sit for 5-10 minutes until foamy. This indicates the yeast is active.
Step 2: In a large mixing bowl, whisk together the all-purpose flour and salt. In a separate medium bowl, whisk together the melted butter, 1/4 cup granulated sugar, eggs, and 1 teaspoon vanilla extract.
Step 3: Add the yeast mixture and the butter-egg mixture to the flour. Mix with a wooden spoon or the dough hook attachment on low speed until a shaggy dough forms.
Step 4: Turn the dough out onto a lightly floured surface and knead for 8-10 minutes, or if using a stand mixer, knead on medium-low speed for 6-8 minutes, until the dough is smooth and elastic. It should spring back when lightly poked.
Step 5: Lightly grease a large bowl with vegetable oil. Place the dough in the bowl, turning once to coat. Cover with plastic wrap or a clean kitchen towel and let rise in a warm place for 1-1.5 hours, or until doubled in size.
Step 6: While the dough is rising, prepare the cinnamon filling. In a small bowl, combine 1/4 cup melted butter, 1/2 cup granulated sugar, and ground cinnamon. Mix until well combined.
Step 7: Once the dough has doubled, gently punch it down to release the air. Turn the dough out onto a lightly floured surface and roll it into a large rectangle, approximately 18×12 inches (45×30 cm).
Step 8: Evenly spread the cinnamon filling over the entire surface of the dough, leaving a small border (about 1/2 inch) on one of the long edges.
Step 9: Starting from the long edge opposite the border, carefully roll the dough tightly into a log. Pinch the seam closed to seal.
Step 10: Carefully transfer the log to a lightly greased standard loaf pan (9×5 inches / 23×13 cm), seam-side down. Cover loosely with plastic wrap or a kitchen towel and let rise in a warm place for another 30-45 minutes, or until nearly doubled in size.
Step 11: Preheat your oven to 375°F (190°C). Once preheated and the loaf has risen, bake for 30-35 minutes, or until golden brown on top and cooked through. If the top starts to brown too quickly, you can loosely tent it with foil.
Step 12: While the bread is baking, prepare the cream cheese glaze. In a medium bowl, whisk together softened cream cheese, powdered sugar, 2 tablespoons milk, and 1/2 teaspoon vanilla extract until smooth and creamy.
Step 13: Remove the sweet bread from the oven and let it cool in the pan for 10-15 minutes before transferring it to a wire rack to cool completely.
Step 14: Drizzle or spread the cream cheese glaze generously over the cooled (or slightly warm) cinnamon swirl sweet bread. Slice and serve!