Berry Blast Protein Muffins

Preheat oven to 180°C and line a 6-cup muffin tray. In a large bowl, whisk together self-raising flour, protein powder, caster sugar, and baking powder. In a separate bowl, combine milk, egg, and olive oil, then pour into the dry ingredients and mix until just combined. Gently fold in the frozen mixed berries. Divide the batter evenly into the muffin cups and bake for 18-20 minutes, or until golden brown and a skewer comes out clean.