Stir together sugar, yeast, salt, and 1 1/2 cups flour in a large mixing bowl.
Combine warm water and oil, and then add it to the mixture.
Stir in egg and beat until smooth.
Add the remaining flour and stir until the dough becomes easy to handle. Turn out the dough onto a floured surface and knead until it becomes a smooth ball.
Lightly grease a large bowl and place the dough in the bowl. Turn the dough a couple of times to coat in oil. Cover and let the dough rise until it has doubled in size, about 1 hour.
Gently press the dough to deflate, and then turn it out on a floured surface. Roll the dough into a 18-inch by 9-inch rectangle.
Combine cinnamon and sugar to make the filling. Brush the dough with melted butter and then sprinkle cinnamon sugar over the dough.
Starting with the 9-inch side of the rectangle, roll the dough and then pinch the edges to seal.
Place dough with the seams facing down in the pan.
Brush the loaf with oil, cover loosely, and let rise until doubled in size, about 1 hour.
Preheat oven to 375° Fahrenheit (190° Celsius) and move rack to the lowest position to ensure a softer crust. Bake for 35 to 40 minutes. The top of the loaf will look golden brown and the bottom will sound hollow when tapped.
Turn loaf out onto a cooling rack and brush with melted butter.