Adapted from Cook’s Illustrated and Smitten Kitchen
Makes about 12 standard-sized muffins

These muffins are best served right out of the oven and spread with room-temperature butter. You can substitute the crème fraîche called for in the recipe with sour cream or plain yogurt; buttermilk might work just as well. To prevent the mixture from turning blue, you may want to toss the berries in a tablespoon of flour, or you can fold in the berries when there is a little bit of flour left in from the dough. Both ways work equally well.