Start by preheating your oven to 350°F (175°C) so it’s fully heated by the time your batter is ready. Prepare a 12-cup muffin pan by either greasing each cup lightly with coconut oil or lining it with paper liners for easy cleanup.

In a medium mixing bowl, add the Greek yogurt, eggs, sweetener, melted coconut oil, and vanilla. Whisk these together slowly at first, then more vigorously until the mixture becomes smooth, creamy, and lump-free. Make sure the coconut oil isn’t too hot, or it may scramble the eggs.

In a separate bowl, stir together the oat flour, vanilla whey protein, baking powder, baking soda, and salt. Mix until the dry ingredients look well combined and no clumps of protein powder remain. This step ensures the muffins rise evenly.

Pour the wet mixture into the bowl of dry ingredients. Using a spatula or wooden spoon, fold the two together gently. Stop mixing as soon as everything looks combined—overmixing can make the muffins dense instead of fluffy.

Add the blueberries to the batter. If you’re using frozen blueberries, add them straight from the freezer without thawing so they don’t turn the batter purple. Fold them in just enough so they’re evenly distributed.

Use a spoon or small scoop to divide the batter evenly into the 12 muffin cups. Each cup should be about two-thirds full. If you want bakery-style domes, you can mound the batter slightly in the center.

Place the muffin pan into the preheated oven and bake for 18–22 minutes, or until the tops turn golden and a toothpick inserted into the center of a muffin comes out clean or with just a few moist crumbs.

Remove the muffins from the oven and let them cool inside the pan for about 10 minutes. This helps them firm up and release more easily. After that, transfer them to a wire rack to finish cooling or enjoy warm and soft right away.