Prep the blueberries. If using fresh or frozen blueberries, add a tablespoon of flour and mix them together. If you are using frozen blueberries, keep the floured berries in the freezer until ready to add at the last second to help prevent the batter from turning purple.
Preheat the oven to 375°F/ 190°C. Line a muffin tray with parchment paper cups or spray with a light coating of neutral flavored spray. Set aside.
Mix the wet ingredients. In a large bowl, whisk together the dairy free milk and apple cider vinegar and let rest for 3 minutes. Then, add the oil, sugar, applesauce, vanilla extract, and a pinch of salt. Whisk until combined.
Add the dry ingredients. Into the same bowl, sift in the flour, protein powder, and baking powder. Switch to a spatula and mix until the batter has come together. A few lumps are okay. Gently fold in the frozen blueberries and lemon zest, making sure not to over mix. Scoop the prepared batter into the muffin tray. Sprinkle a few extra blueberries on top.
Bake. Bake in the prepared oven with the rack in the middle of the oven for 22-24 minutes or until a toothpick inserted into the center pulls out clean. When done, let them cool on a cooling rack for at least 15 minutes. Serve and enjoy!
