Preheat your oven to 350°F. Line a 24-count mini muffin pan with mini cupcake liners.
In a medium bowl, whisk the flour, baking powder, and salt.
In a larger bowl, whisk the oil, sugar, egg, vanilla extract, sour cream, and whole milk until smooth and well combined. Add the dry ingredients and whisk until the batter is smooth. Gently fold the fresh blueberries into the batter.
Scoop the batter evenly into the cupcake liners and bake in the preheated oven for 15-17 minutes, or until a toothpick comes out clean.
Let the muffins cool slightly in the pan before removing and serving.