Directions

• Heat oven to 350° F. Grease your loaf pan (you'll want one that's at least 3 inches deep) with butter and coat with a thin dusting of flour.
• For the streusel: Melt 1/4 cup of butter. Stir in the 1/2 cup sugar, 1/3 cup flour, and 1/4 teaspoon salt. Mix in the nuts. Set aside.
• For the cake: Place the 1/2 cup of butter in a medium pan over medium heat. Once it's melted, don't walk away. Take it off the heat once the sizzling stops (4 to 5 minutes) and brown bits drop down to the bottom of the pan. Set aside to cool.
• Whisk together the flour, baking soda, baking powder, and salt. Set aside.
• In the bowl of your food processor, combine the brown butter, bananas, eggs, brown sugar, white sugar, yogurt, orange juice, and vanilla extract. Blend until almost smooth (about 15 seconds). If you see any chunks of banana, pulse for a few more seconds.
• Pour the wet ingredients over the combined dry ingredients. Carefully fold together. Make sure to incorporate all of the flour pockets but be careful not to overmix. Spoon into your greased loaf pan. Pour the streusel all over the top of the batter. Using your fingers or a spoon, gently press some of the streusel a few inches down into the batter. Place on a sheet pan in the middle of your preheated oven. Don't worry if it overflows a bit. It will look cool and still taste great.
• The cake is done when you stick a skewer or paring knife about an inch from the center of the cake and it comes out clean. The very center should still be gooey. This takes between 35 and 40 minutes. Since all ovens are different, start checking after about 25 minutes.
• Remove from the oven and let it cool for about 30 minutes. Then eat with butter, cream cheese, or a large scoop of vanilla bean ice cream. If you eat it the next day, make sure to warm it up or toast it and then slather it with butter. Freezes beautifully for a few months.