Preheat your oven to 350°F (175°C) and line a muffin tin with paper liners.
In a mixing bowl, whisk together the flour, sugar, baking powder, and salt.
In another bowl, mix the vegetable oil, milk, and eggs until well combined.
Pour the wet ingredients into the dry ingredients and stir until just combined.
Fill each muffin cup halfway with the batter, then add a teaspoon of Nutella in the center of each. Top with more batter until the cups are about ¾ full.
Bake for 20 minutes or until a toothpick inserted into the center comes out clean.
Let the muffins cool in the tin for 5 minutes, then transfer to a wire rack to cool completely.