Preheat the oven to 400˚ F. Line a baking sheet with foil. Spread the berries out on the baking sheet, sprinkle with a pinch of sugar and toss gently to mix. Roast, stirring once or twice, until the berries are tender and have released most of their juices, about 20-22 minutes. Place a colander or strainer over a bowl or liquid measuring cup and strain the berries, reserving the excess juices. You will have approximately 4 tablespoons (¼ cup) of juice. Add just enough milk to make 6 tablespoons total of liquid if you are short on juice.
Lower the oven temperature to 350˚ F. Line muffin pans with paper liners. In a medium bowl, combine the sugar, flours, baking powder and salt. Whisk to blend. In a large mixing bowl, combine the reserved strawberry juice/milk, greek yogurt, eggs, and vanilla extract. Whisk until smooth. Whisk in the melted butter. Add the dry ingredients to the bowl with the wet ingredients and whisk just until combined and no dry streaks remain. Fold in the strawberries with a spatula.
Divide the batter between the prepared muffin liners. Sprinkle the tops with coarse sugar, if desired. Bake, rotating the pans halfway through, until the muffins are set and a toothpick inserted in the center comes out clean, about 18-20 minutes. Transfer to a wire rack and let cool.
*I prefer to use half white whole wheat flour in nearly all baked goods we eat for breakfast, but you can use all all-purpose flour if you wish.