These bakery style banana muffins are the best around! They are buttery and moist with a profound banana flavor, and a deliciously crumbly walnut streusel topping. For professional bakery muffins, they are a cinch to make at home.
4.2grams(1 ½ teaspoons) kosher salt(preferably Diamond Crystal brand for correct weight/volume conversion—if using Morton kosher salt reduce to ¾ teaspoon to yield approximately the same weight)
120grams(4.2 ounces) unsalted butter, at room temperature
144grams(¾ cup) lightly packed light brown sugar
80grams(¼ cup + 1 tablespoon) eggs
7grams(1 ⅛ teaspoons) vanilla paste
24grams(1 tablespoon + 2 teaspoons) creme fraiche (I use sour cream)
256grams(1 cup) mashed banana (about 2 large bananas)
Walnut Streusel Topping:
25grams(3 tablespoons) all-purpose flour
25grams(2 tablespoons) granulated sugar
25grams(3 ½ tablespoons) walnuts, very finely chopped(use a small food processor)
Pinchkosher salt
25grams(1 ¾ tablespoons) cold unsalted butter, cut into ¼-inch pieces
Instructions
For the muffins: whisk the flour, baking soda, baking powder, and salt in a medium bowl.
Place the butter in the bowl of a stand mixer fitted with the paddle attachment, turn to medium-low speed, and cream the butter until it has the consistency of mayonnaise. Add the sugar and mix for 1 to 2 minutes, until fluffy. Scrape down the sides and bottom of the bowl, add the eggs and vanilla paste, and mix for 15 to 30 seconds on low speed, until just combined.
Add the dry ingredients in 2 additions, mixing on low speed for 15 seconds each, or until just combined. Scrape the bottom of the bowl to incorporate any dry ingredients that have settled there. Add the creme fraiche and banana and mix on low speed for about 30 seconds until just combined. Transfer the batter to a covered container and refrigerate overnight, or for up to 36 hours.
To make the streusel topping: combine the all-purpose flour, walnuts, sugar and salt in a bowl and whisk to break up any lumps. Add butter and toss to coat the pieces. Work the mixture with your fingertips, breaking the butter into pieces no larger than ⅛ inch and combining it with the flour mixture. Do not overwork the mixture or allow the butter to become soft; if it does, place the bowl in the refrigerator to harden the butter before continuing.
Transfer the streusel to a covered container or a resealable plastic bag. Refrigerate for at least 2 hours, or up to 2 days, or freeze for up to 1 month. Use the streusel while it is cold.
To bake the muffins: Preheat the oven to 425°F. Line a 6-cup jumbo muffin pan with muffin papers and spray the papers with nonstick cooking spray, or alternatively line 13 cups in two standard muffin pans (space them out between the pans) with paper liners.
Spoon the batter evenly into the papers (use an ice cream scoop if you have one), stopping ½ inch from the top. Divide the streusel over the tops of the muffins.
Place the pan in the oven, lower the temperature to 325°F, and bake for 35 to 38 minutes for jumbo muffins or 29 to 32 minutes for standard muffins, until the muffins are golden brown and a skewer inserted in the center comes out clean. Set the pan on a cooling rack and cool completely.
Notes
I have tested the kosher salt conversion MULTIPLE times for this recipe using my digital scale and it is correct. It may vary if you use different brands of kosher salt because the size of the crystals may vary. I use Diamond Crystal brand (the same that Bouchon Bakery uses), and ¼ teaspoon of this brand of kosher salt is 0.7 grams. If you multiply by 6 to yield 1 ½ teaspoons you will get 4.2 grams (the amount called for in the recipe). Other brands of kosher salt like Morton weigh differently. According to the Morton kosher salt box ¼ teaspoon of their salt weighs 1.2 grams. This would convert to a little more than ¾ teaspoon for the same weight. As you can see different brands can vary greatly. This is why weighing your ingredients will always be the most accurate way to bake.
The muffins are best the day they are baked, but they can be wrapped individually in a few layers of plastic wrap or stored in a single layer in a covered container at room temperature for up to 3 days or frozen for up to 1 week. Defrost the muffins still in the container so any condensation will form on the outside of the container and not on the muffins. Place on a sheet rack and refresh in a 325°F oven for about 5 minutes, if desired.
If you don't have cake flour, you may substitute additional all-purpose in its place. I have made these muffins both ways, and the results were good in either case.
To measure the eggs, simply beat eggs one at a time in a bowl and then transfer to a measuring cup (or into a bowl on a digital scale) until you have enough beaten egg.
For scooping the muffin batter I use this Oxo ice cream scoop which is a #12 size, with a 2 ½ fluid ounce capacity. A slightly scant scoop of this size is a good amount for a standard muffin cup.
After dividing the muffin batter into the muffin cups, I like to use wet fingers (just run your hand under the faucet for a few seconds and then shake it off) to press down on the dough to flatten and fill the cups. This way your fingers won't stick to the batter, you can ensure the cups are filled evenly (if you are spooning the batter instead of scooping with a uniform-sized scoop) and you can comfortably and evenly top the batter with streusel.