50

min
  • desserts

Bayesian Brown Butter Banana Blondies

These brown butter banana blondies are rich, chewy, deeply aromatic, and just a little unexpected. Ripe banana brings natural sweetness and moisture, brown butter adds toasted nuttiness, and a touch of white miso sharpens the caramel notes without making the bars taste savory. Finished with dark chocolate and a sesame-sugar crunch, they’re the kind of dessert that feels familiar at first bite, then gets more interesting as you keep eating.

  • SERVES
    16 people
  • PREP TIME
    20 minutes
  • Cook TIME
    30 minutes
Ingredients
  • ¾ cup unsalted butter
  • 1 cup packed light brown sugar
  • ¼ cup granulated sugar
  • 1 large ripe banana, mashed
  • 1 large egg plus 1 egg yolk, room temperature
  • 2 teaspoons vanilla extract
  • 1 tablespoon white miso paste
  • 1 tablespoon dark rum or bourbon, optional
  • 1 ½ cups all-purpose flour
  • ¾ teaspoon baking powder
  • ½ teaspoon kosher salt
  • ¼ teaspoon ground cinnamon
  • ⅛ teaspoon ground nutmeg
  • ¾ cup chopped dark chocolate or bittersweet chocolate chips
  • ½ cup toasted walnuts or pecans, roughly chopped
  • 1 tablespoon sesame seeds
  • 1 tablespoon turbinado sugar or coarse sugar
  • Flaky sea salt, for finishing
Directions

  1. Preheat the oven to 350°F. Line an 8x8-inch baking pan with parchment paper, leaving overhang on two sides for easy removal.

  2. Brown the butter in a light-colored saucepan over medium heat. Stir often as it melts, foams, and turns golden brown with a nutty aroma. Once browned, immediately pour it into a large mixing bowl, scraping in the toasted bits. Let cool for 8 to 10 minutes.

  3. Add the brown sugar and granulated sugar to the warm brown butter. Whisk until glossy and well combined.

  4. Whisk in the mashed banana, egg, egg yolk, vanilla extract, white miso, and rum or bourbon if using. Mix until smooth and thick.

  5. In a separate bowl, whisk together the flour, baking powder, kosher salt, cinnamon, and nutmeg.

  6. Fold the dry ingredients into the wet ingredients until just combined. Do not overmix.

  7. Fold in the dark chocolate and toasted nuts, reserving a small handful of each for the top if desired.

  8. Spread the batter evenly into the prepared pan. Scatter the reserved chocolate and nuts over the top, then sprinkle with sesame seeds, turbinado sugar, and a small pinch of flaky sea salt.

  9. Bake for 28 to 32 minutes, or until the edges are set, the top is golden, and a toothpick inserted near the center comes out with a few moist crumbs. Avoid overbaking; blondies should remain chewy.

  10. Cool completely in the pan before lifting out and slicing into squares. For the cleanest cuts, chill for 20 minutes before slicing.

Blondies are often described as brownies without cocoa, but the best ones have their own identity: buttery, caramel-forward, chewy at the edges, and tender in the center. This version leans into that richness by starting with brown butter, which gives the bars a toasted hazelnut aroma and a deeper flavor than melted butter alone. Banana adds moisture and a mellow fruitiness, making the blondies soft without turning them cakey.

The “Bayesian” idea comes from building flavor in layers, adjusting the recipe as new evidence appears: a riper banana means more sweetness, brown butter means more nuttiness, miso means more depth. Instead of relying on one bold ingredient, these blondies use small, strategic additions to make the whole dessert taste more complete.

The inspiration behind this recipe is the idea of updating a classic blondie with every bite: first caramel, then banana, then chocolate, then a quiet savory note that makes you want another square.

White miso is the Iron Chef-style twist here. It does not dominate the dessert; instead, it behaves almost like a salted caramel enhancer, balancing the sugar and amplifying the browned butter. Toasted sesame seeds on top add a delicate crunch and a subtle roasted flavor that makes the blondies feel more polished than the average bake-sale bar.

Dark chocolate keeps the sweetness in check, while walnuts or pecans provide structure and contrast. If you prefer a softer, sweeter blondie, use milk chocolate and skip the nuts. If you want a more grown-up version, keep the dark chocolate, add the splash of rum or bourbon, and finish generously with flaky salt.

These bars are excellent the day they’re baked, but even better after a few hours of resting. The banana, butter, and brown sugar settle into a dense, fudgy texture that slices beautifully and tastes like banana bread met salted caramel in a test kitchen.

desserts