I used fresh berries for these but I'm sure you can use frozen ones too, as long as they're thawed and drained well. I know some people don't like to bake with strawberries because they get a little squidgy, but I've never minded the texture change, and you shouldn't either.
Makes 12 regular muffins
Butter for greasing pan
2 C all-purpose flour
1/4 C sugar
1 Tbsp baking powder
1/2 tsp salt
1/4 C butter, melted and cooled
1 C milk, at room temperature
1 egg, beaten lightly
3/4 total berries; if using strawberries, hull and dice them
turbinado sugar, for topping (optional)
Generously butter a 12-muffin pan and preheat the oven to 425F.
In a large bowl, whisk together the flour, sugar, baking powder, and salt. Stir in the fruit. In a separate bowl combine the melted butter, milk, and egg. Make a well in the center of the dry ingredients and pour in the wet ingredients. Using a wooden spoon, combine until just moistened.
Divide batter into the muffin pan, filling each cup about 2/3 of the way full (a large ice cream scoop is an awesome tool for this). Sprinkle a little turbinado sugar, if using, on top of each muffin. Bake for about 18-20 minutes, or until the tops are puffed and golden brown. Cool the pan in a cooling rack for 5 minutes before removing the muffins from the tin. Eat them all at once, and take a giant nap.