Prepare for Baking:
Preheat your oven to 375°F (190°C). Line a muffin tin with paper liners or grease it with non-stick spray.
Mix the Dry Ingredients:
In a large bowl, whisk together the flour, baking powder, baking soda, salt, granulated sugar, and brown sugar until well combined.
Combine Wet Ingredients:
In another bowl, whisk together the melted butter, eggs, vanilla extract, and buttermilk until smooth.
Create the Batter:
Gradually add the wet ingredients to the dry ingredients, mixing gently until just combined. Avoid overmixing to ensure the muffins remain tender.
Fold in Strawberries:
Gently fold the diced strawberries into the batter, being careful not to crush them.
Fill the Muffin Tin:
Divide the batter evenly among the muffin cups, filling each about 3/4 full.
Bake the Muffins:
Place the muffin tin in the preheated oven and bake for 18-22 minutes, or until a toothpick inserted into the center of a muffin comes out clean.
Cool and Serve:
Remove the muffins from the oven and allow them to cool in the tin for 5 minutes before transferring them to a wire rack to cool completely.