Line a loaf pan with parchment paper (or use a silicone loaf pan).
Mix egg whites with honey.
Add psyllium husks, protein powders, oat flour, and salt. Mix well.
Bake for 50-55 minutes.
Let cool, and enjoy!
Store in the refrigerator or freezer.
Notes
A note about substitutions: You can replace the rice protein powder with more pea protein powder, but I wouldn't try other substitutions. Also, keep in mind that my loaf pan is 8.5 x 4.5 x 2.5 inches; if yours is much bigger, you may want to scale the recipe up.