Preheat your oven to 375°F and line a baking sheet with parchment paper.
Mix self-rising flour, Greek yogurt, protein powder and cinnamon together until a dough starts to form.
Mix in the finely diced apple. If the dough feels a little sticky, add a sprinkle of flour until it’s easy enough to work with! If it’s too dry, add more yogurt.
Divide the dough into 12 pieces and roll each one into a ball.
Place on your baking sheet, whisk 1 egg with about 1 teaspoon of water or milk, then lightly brush the tops right before baking and bake for about 15–18 minutes, or until lightly golden and cooked through.
While they’re still warm, lightly brush each donut hole with melted butter or coconut oil. I used spray coconut oil and it worked perfectly! You just want them a little wet so the coconut sugar sticks.
Mix the coconut sugar and cinnamon together, then roll each donut hole in the cinnamon sugar mixture.
To store, I just kept them in an air tight container in the fridge and microwaved them for like 15 sec before eating
