01 - Preheat oven to 400°F. Line standard 12-cup muffin tin with paper liners or grease thoroughly.
02 - Whisk together flour, baking powder, baking soda, and salt in a large bowl until well blended.
03 - Whisk oil or melted butter, sugar, eggs, milk, and vanilla extract in separate bowl until fully incorporated.
04 - Pour wet ingredients into dry ingredients. Stir gently until just combined—avoid overmixing to ensure tender texture.
05 - Fold in diced strawberries carefully until distributed evenly throughout batter.
06 - Divide batter evenly among prepared muffin cups, filling each approximately ¾ full.
07 - Sprinkle coarse sugar generously over tops of each muffin.
08 - Bake for 22 to 25 minutes until toothpick inserted in center comes out clean and tops are golden brown.
09 - Let cool in pan for 5 minutes, then transfer to wire rack to finish cooling.