01 - Preheat oven to 350°F. Generously grease a bundt pan or deep round baking dish with cooking spray or butter.
02 - Combine almond flour, protein powder, baking powder, and salt in a large mixing bowl. Whisk thoroughly to eliminate any lumps.
03 - In a separate bowl, whisk Greek yogurt, eggs, almond milk, melted coconut oil, and vanilla extract until completely smooth and incorporated.
04 - Pour wet ingredients into dry mixture. Stir with a spatula until soft dough forms, being careful not to overmix.
05 - Mix erythritol and cinnamon in a small bowl until evenly combined. Melt butter or coconut oil in a separate shallow dish.
06 - Pinch off approximately 1-inch pieces of dough and roll into balls. Dip each ball in melted butter or coconut oil, then roll thoroughly in cinnamon mixture until coated.
07 - Layer coated dough balls in prepared pan, leaving slight space between pieces for expansion during baking.
08 - Bake for 25-30 minutes until golden brown and set. A toothpick inserted should come out clean.
09 - Allow to cool in pan for 10 minutes before removing.
10 - Whisk Greek yogurt, powdered erythritol, and vanilla extract until smooth and drizzle over warm bread immediately before serving.