Brown the Butter
Place butter in a light-colored, heavy-bottomed saucepan over medium heat.
Allow butter to melt completely, swirling occasionally.
Continue cooking as butter foams and sputters. This is water evaporating - a crucial step for concentration of flavor.
Watch carefully as milk solids settle to the bottom and begin turning golden brown (about 5-7 minutes).
When butter smells nutty and has amber-colored specks, immediately remove from heat.
Pour into a heat-safe bowl, making sure to scrape in all the browned bits. Allow to cool until still liquid but not hot, about 15 minutes.
Prepare Your Equipment
Preheat oven to 350°F (175°C).
Grease a 9×5-inch loaf pan with a small amount of reserved browned butter.
Line with parchment paper, leaving overhang for easy removal.
Mix the Wet Ingredients
In a large bowl, whisk together ¾ cup cooled brown butter, maple syrup, and brown sugar until smooth and no sugar lumps remain.
Add eggs one at a time, incorporating fully after each addition.
Stir in vanilla extract.
Fold in pumpkin puree until completely incorporated.
Combine Dry Ingredients
In a separate bowl, whisk together flour, baking soda, baking powder, salt, and all spices.
Create the Batter
Gradually add dry ingredients to wet ingredients, folding gently with a spatula.
Mix just until no dry streaks remain – avoid overmixing.
Bake to Perfection
Transfer batter to prepared loaf pan, spreading evenly to corners.
Tap pan gently on counter to remove any large air bubbles.
Bake for 55-65 minutes, or until a toothpick inserted in center comes out with a few moist crumbs.
If top browns too quickly, tent loosely with aluminum foil after 40 minutes.
Cool and Glaze
Allow bread to cool in pan for 15 minutes.
Use parchment overhang to lift bread onto cooling rack.
Cool completely before glazing (at least 1 hour).
For glaze, whisk together maple syrup, powdered sugar, 2 tablespoons browned butter, and salt.
Add cream as needed for desired consistency.
Drizzle over cooled bread and allow to set before slicing.