Preheat oven to 350°F (180°C). Line a 9x5-inch loaf pan with foil or parchment and spray with cooking spray.
To a bowl, add gluten free 1-to-1 baking flour, baking powder, and salt. Whisk to combine.
In a separate bowl, whip up the egg yolks with a hand mixer until fluffy. Mix in milk and oil and continue to beat until well-integrated.
Add dry mixture into the wet and mix well with hand mixer, until relatively smooth. Set aside.
Separately, whip up the egg whites to medium peaks. (Again, I use a hand mixer to do this.)
Using a rubber spatula, gently fold the whipped egg whites into batter—but don’t over-mix! (This is going to help the bread rise and maintain its lift without yeast or gluten.)
Transfer batter to prepared loaf pan and bake for about 45-60 minutes, until a toothpick comes out clean.
Allow to cool completely before slicing and enjoying!