Preheat oven to 350°F. Line a standard loaf pan with parchment paper or grease it thoroughly.

Add the eggs, Greek yogurt, and melted butter or coconut oil to a large mixing bowl and whisk until smooth and fully combined.

Sprinkle in the baking powder, salt, and xanthan gum or psyllium husk powder and whisk until evenly incorporated with no clumps.

If using almond flour, fold it into the batter with a spatula just until combined.

Pour the batter into the prepared loaf pan, smooth the top with a spatula, and tap the pan lightly on the counter to release air bubbles.

Bake for 35 minutes, or until the top is lightly golden and a toothpick inserted in the center comes out clean or with a few moist crumbs.

Place the pan on a cooling rack and let the bread cool in the pan for 10 minutes.

Remove the loaf from the pan and transfer to the rack to cool completely before slicing and serving.