Preheat the oven to 350° and spray a 9" x 5" loaf pan. Combine the flour, sugar, baking soda and salt in a mixing bowl. In a separate bowl, combine the milk, egg and oil. Stir the wet ingredients into the dry ingredients until just combined. In a separate small bowl, combine the 1/2 cup sugar with the ground cinnamon. Pour half of the batter into the loaf pan, and sprinkle a layer of cinnamon sugar. Repeat this process with the rest of the batter, topping it with cinnamon sugar. Using a skewer or knife, swirl the cinnamon sugar into the batter.

Bake for 50 minutes or until a toothpick comes out clean. If the loaf is getting too brown on top, cover it loosely with a tent of foil.

While it is baking, make the vanilla glaze by mixing together the milk, powdered sugar and vanilla. Drizzle it over the bread, allowing at least 30 minutes to cool before serving.