In the bowl of a stand mixer, add the pineapple juice, water, melted butter, 2 eggs, 1 egg yolk (reserve the egg white), brown sugar, and vanilla. Mix on medium speed for 1 minute, until fully combined.
In a medium bowl, whisk together the gluten free flour mix, potato flour, coconut flour, instant yeast, psyllium husk powder, baking powder, xanthan gum, and salt.
Add the dry ingredients to the wet ingredients and beat on low speed for 30 seconds. Stop and scrape down the bowl.
Turn the mixer up to medium and mix for 3 minutes, until the batter looks fluffy and pale.
Meanwhile, prepare an 8” x 4.5” baking pan by spraying generously with cooking spray.
After the dough is done mixing, scoop the batter into the prepared pan and smooth the top.
Cover the pan with a tea towel and let rise until batter barely crests the top of the rim or about 30 minutes.
At the 20 minute mark, preheat the oven to 350 F.
Mix the reserved egg white and use a pastry brush to spread over the dough.
Bake for 45 minutes or until an instant-read thermometer registers between 205-210F. You may need to cover it with foil at the 40 minute mark.
After it’s finished baking, let the loaf cool in the pan on a wire rack for 15 minutes.
Remove the bread from the pan and lay it on its side and let it cool an additional 15 minutes. Then flip to the other side and cool an additional 15 minutes.
Let cool for 3 hours before slicing.
Notes
Make sure to weigh the ingredients rather than measure by cups.
Separate the eggs and reserve the egg white for the egg wash on the rise dough.
The rise time should be judged by when the dough gets close to the top of the pan. This could take between 20-40 minutes. Begin preheating the oven at the 20-minute mark.
Let the bread cool completely before slicing into it.
To make Gluten Free Hawaiian Rolls:
Follow the recipe as written, but instead of scraping the batter into a loaf pan, spray a 9"x13" pan with non-stick spray and portion ⅓ cup of batter in 3 long rows and 4 short rows for 12 rolls total.
Let the rolls rise for 30-60 minutes or until the rolls rise by 50%.
Spread the egg white on the risen rolls.
Bake at 375F for 20-25 minutes or until an instant-read thermometer registers 205-210F.