Preheat oven to 350 degrees Fahrenheit (or 175 degrees Celsius). Grease two standard loaf pans with butter, or line them with parchment paper.

In a large mixing bowl add the yellow cake mix, self-rising flour, and cinnamon. Stir to mix the dry ingredients evenly.

Add the wet ingredients: Pour in the lightly beaten eggs (I beat them in a small bowl first) and the entire can of apple pie filling. Stir gently until everything is just combined, it’s okay if the pie filling breaks up a little.

Fold in the finely diced fresh apple into the batter. Divide the batter evenly between the two prepared loaf pans.

Sprinkle the top of the batter with the sugar (or brown sugar) for a sweet, slightly crunchy topping. Bake for 45–55 minutes, or until a toothpick inserted into the center comes out clean or with just a few moist crumbs.

Cool the bread in the pans for about 10–15 minutes, then transfer to a wire rack to cool completely to room temperature. Slice and serve.