Grease the insert of your slow cooker and line it with a grease-proof liner or foil, creating handles for easy removal.

Brown the butter: Melt 1/2 cup unsalted butter in a saucepan over medium heat, stirring until foaming subsides and tiny brown bits form. Remove and cool for 10 minutes.

In a large mixing bowl, cream the cooled brown butter with brown sugar and granulated sugar until light and fluffy, about 3 minutes.

Add eggs one at a time, beating well after each. Mix in mashed bananas, vanilla extract, and almond extract.

In a separate bowl, whisk together flour, baking soda, and salt.

Alternately add the flour mixture and milk to the wet ingredients, mixing until just combined. Do not overmix.

Pour the batter into the prepared slow cooker. Add sprinkles on top if desired.

Cover and cook on low for 4 hours or until a toothpick inserted in the center comes out clean or with a few moist crumbs. (Check after 3.5 hours to avoid overcooking.)

Remove the loaf from the slow cooker using the liner handles and let it cool completely on a rack.

For the glaze, whisk together powdered sugar, milk or cream, and extract until smooth. Drizzle over the cooled loaf.