Begin by warming your milk. Use a thermometer to ensure it reaches 95 to 125°F. This temperature range is perfect for activating the yeast without killing it.
In a large mixing bowl, combine the warm milk, melted butter, and the lightly beaten egg. Stir until combined and let it sit for a few minutes to cool slightly if it feels too hot.
Sprinkle the instant dry yeast over the liquid mixture. Add the granulated sugar and let it sit for about 5-10 minutes, or until it becomes frothy.
In another bowl, whisk together the bread flour, ground cinnamon, and salt (if using). Gradually add this mixture to the wet ingredients, stirring until a shaggy dough forms.
Transfer the dough to a lightly floured surface and knead for about 8-10 minutes. The dough should become smooth and elastic. During the last few minutes of kneading, incorporate the raisins into the dough.
Place the kneaded dough into a greased bowl, cover it with a clean kitchen towel, and let it rise in a warm place until doubled in size, about 1-2 hours.
Once risen, punch down the dough to release the air. Turn it out onto a floured surface and shape it into a loaf. Place the shaped dough into a greased loaf pan.
Cover the loaf pan with the towel again and let it rise for another 30-45 minutes, or until it has risen slightly above the rim of the pan.
While the dough is rising for the second time, preheat your oven to 350°F (175°C).
Once the dough has risen, place the loaf in the preheated oven and bake for 30-35 minutes, or until the top is golden brown and the bread sounds hollow when tapped.
After baking, remove the bread from the oven and allow it to cool in the pan for about 10 minutes. Then, transfer it to a wire rack to cool completely before slicing.
