Preheat your oven to 200 degrees then shut it off. This will create a warm environment for your bread to rise.

Grease a 9x5 loaf pan with shortening.

Dust 2 rectangular pieces of parchment paper with flour and set a side.

Make the filling. In a small bowl whisk together the brown sugar and cinnamon.

Add the room temperature butter and mix it all with a spatula or electric mixer into a paste. Set aside.

In a small bowl whisk together the bread flour, xanthan gum, sugar, yeast, baking powder and salt. Set aside.

In a large mixing bowl whisk together the melted butter, egg and apple cider vinegar until combined.

Add the flour mix and warm water and using an electric/stand mixer with dough attachment, mix it all into a dough. Use your hands to continue forming dough if necessary.

Transfer the dough onto one piece of the flour dusted parchment paper. Use your hands to flatten the dough and begin forming it into a rectangle. Flip the dough so that both sides are flour dusted.

Place the other piece of parchment paper over the top and use a rolling pin to roll the dough about 1/2 inch thick (or a little less) rectangle. Remove the top piece of parchment paper.

Using your hands (the warmth of your fingers softens the butter more and makes it easier to spread), evenly spread the paste filling onto the dough. Do not spread it too close to the edges.

Starting on one of the long ends of the rectangle, carefully pick up the edges and begin tightly and carefully rolling the dough into a log. Pinch the seam to seal the edges.

With the seam underneath the roll cut the roll down the middle lengthwise using a sharp knife.

Carefully criss cross-cross one half on top of the other half forming an X and tightly roll/twist the two together. Do not pick up the pieces as the dough is delicate and may break. Smooth out any cracks.

Carefully place the log into the prepared loaf pan. You may have to smoosh it together a big to fit if your log is too long.

Cover the loaf pan with plastic wrap and aluminum foil and place it in the warmed oven for 2 hours.

When the bread is done rising, remove it from the oven take the aluminum and plastic wrap off.

Lower oven rack to third lowest position and preheat the oven to 350 and prepare the topping.

In a small bowl whisk the brown sugar, cinnamon and flour together. Add the melted butter and stir until combined.

Spoon it over the loaf of bread.

When the oven is preheated bake the loaf for 42-45 minutes. All ovens are different, if you bread begins to brown too quickly, tent a piece of foil over the top after 20 minutes. (I did not have to do this).

Let the bread cool for about 20 minutes. Carefully remove it from the pan, slice and serve warm.

Store covered in an airtight container. Reheat leftover slices for up to 3 days.