Pre-heat our oven to 350 degrees and prepare a bread pan (about 9×5 inches) by spraying it with non-stick cooking spray or lightly greasing it with butter.In a large bowl combine flour, baking powder, salt, and sugar. In a small bowl combine egg, milk, vanilla extract and yogurt or sour cream.Add the dry ingredients into the wet and stir to combine. You can use a large wooden spoon for this if you wish, no mixer is required.In a small bowl combine swirl ingredients together – 1/3 cup sugar, 2 teaspoons cinnamon and 2 tablespoons water. Use a tablespoon to drop spoonfuls of this mixture over the bread, then use a knife to make swirl designs to incorporate the cinnamon mixture into the bread.Bake for 45-50 minutes or until you insert a toothpick and it comes out clean.Remove the bread from the oven and transfer it to a cooling rack to cool for 15 minutes.Meanwhile, make the glaze ingredients by combining 1/2 cup powdered sugar with 1 tablespoon milk.Remove the bread from the pan and allow it to continue cooling completely.When the bread has completely cooled, pour the glaze over the top and serve.Enjoy!