113gunsalted buttermelted and slightly cooled (½ cup)
150glight brown sugarpacked (¾ cup)
50ggranulated sugar¼ cup
2large eggsroom temperature
1tablespoonvanilla extract
230gbananamashed and very ripe (1 cup)
120gfull-fat sour cream½ cup
60gwhole milk¼ cup
250gfresh blueberries1 ¾ cups
1tablespoonall-purpose flourfor tossing with the blueberries
35gadditional fresh blueberries¼ cup for topping
Turbinado sugarfor topping
Instructions
Preheat the oven to 425°F (218°C). Line a standard 12-cup muffin pan with paper liners.
In a medium bowl, whisk together the flour, baking powder, baking soda, salt, and cinnamon.
250 g all-purpose flour, 1 teaspoon baking powder, 1 teaspoon baking soda, ¾ teaspoon fine sea salt, ½ teaspoon ground cinnamon
In a large bowl, whisk together the melted butter, brown sugar, and granulated sugar.
113 g unsalted butter, 150 g light brown sugar, 50 g granulated sugar
Add the eggs and vanilla and whisk until smooth and well combined. Whisk in the mashed banana, sour cream, and milk.
2 large eggs, 1 tablespoon vanilla extract, 230 g banana, 120 g full-fat sour cream, 60 g whole milk
Add the dry ingredients to the wet ingredients. Fold gently with a rubber spatula until just a few streaks of flour remain.
Toss the blueberries with 1 tablespoon flour, then gently fold them into the batter. Stop mixing as soon as the batter is combined.
250 g fresh blueberries, 1 tablespoon all-purpose flour
Let the batter rest at room temperature for 15 minutes. This helps thicken the batter and encourages taller muffin tops.
Divide the batter evenly between the 12 muffin cups, filling them all the way to the top with the batter slightly mounded. Press a few additional blueberries onto each muffin and sprinkle generously with turbinado sugar.
35 g additional fresh blueberries, Turbinado sugar
Bake at 425°F for 5 minutes. Without opening the oven door, reduce the temperature to 350°F (177°C) and bake for another 15-19 minutes, or until the muffins are deeply golden and a toothpick inserted into the center comes out clean or with a few moist crumbs.
Let the muffins cool in the pan for 10 minutes before transferring them to a wire rack.
Notes
Fill the muffin wells completely; this batter is intentionally thick enough to mound slightly above the liners before baking.
The initial blast of heat at 425°F helps the muffins rise quickly and create tall domes.
Use very ripe bananas and full-fat sour cream. The combination of banana, sour cream, brown sugar, and melted butter keeps these muffins soft and moist for several days.
Do not overmix the batter; fold only until the flour disappears.
Measure the mashed banana if possible; 230 g gives plenty of banana flavor and moisture without making the muffins gummy or overly heavy.
Fresh blueberries work best for tall, clean-looking bakery muffins. If using frozen, add them directly from the freezer and expect the batter to turn slightly purple in places.