Preheat oven to 350°F. Lightly grease 15 standard muffin cups or line with paper muffin cups.
In a large bowl, whisk together the flour, sugar, baking powder, salt, and cinnamon.
In a separate bowl, whisk together the oil, melted butter, vanilla extract, eggs, and milk.
Make a well in the center of the dry ingredients. Pour the wet ingredients into the dry ingredients; mix just until combined (be careful not to overmix).
Gently fold in the strawberries.
With a large ice cream scoop or spoon, fill the prepared muffin cups about 2/3 full with batter. Sprinkle the tops with coarse sugar.
Bake for 25 minutes, until the tops are golden brown and a toothpick inserted in the center of a muffin comes out clean. Remove from the oven and let cool in the pan for 5 minutes.
Transfer the muffins to a wire rack to cool. Enjoy warm or at room temperature.