Step 1: Preheat your oven to 375°F (190°C). Line a baking sheet with parchment paper.
Step 2: In a large bowl, whisk together the self-rising flour and salt (if adding separately). Make a well in the center and add the Greek yogurt. Mix with a spoon or your hands until a shaggy dough forms.
Step 3: Turn the dough out onto a lightly floured surface. Knead for 5-8 minutes until the dough is smooth and elastic. It should be slightly tacky but not sticky.
Step 4: Divide the dough into 4 equal pieces. Roll each piece into a 7-8 inch long rope. Join the ends of each rope to form a bagel shape, pinching firmly to seal. Alternatively, form a ball and poke a hole through the center, stretching it gently to create a 1-inch diameter hole.
Step 5: In a small bowl, whisk the egg white with 1 tablespoon of water to create an egg wash. Place the shaped bagels on the prepared baking sheet. Brush the tops and sides of each bagel generously with the egg wash.
Step 6: Sprinkle your desired toppings generously over the egg-washed bagels.
Step 7: Bake for 20-25 minutes, or until the bagels are golden brown and sound hollow when tapped on the bottom.
Step 8: Transfer the baked bagels to a wire rack to cool slightly before slicing and serving. Enjoy your homemade high-protein bagels!