Pre heat oven to 375ºF. Grease a 12-cup muffin pan, or line with muffin cups.
In a large bowl, mix flour, sugar, and baking powder. Set aside.
In a medium bowl, beat the egg. Then add milk, melted butter, and vanilla yogurt. Make sure the mixture has fully combined.
Pour the liquid mixture into the large bowl, and blend with a wooden spoon or electric mixture until there are no more lumps. The toss in and fold the strawberries gently, making sure not to smush them.
Fill each muffin cup 2/3-3/4 full. (Optional) equally divide one tablespoon of butter (diced in small cubes) over each muffin cup.
Bake the muffins for 23-25 minutes. Cool for 5-10 minutes before serving.