Preheat the oven to 350°F.
Add the butter to a pan on medium heat. Work low and slow to let the butter melt, come to a slight fizz, and then brown slightly. This will take about 4-5 minutes. When you see the milk solids separate and start to brown at the bottom of the pan, turn off the heat and add the sage. The sage will sizzle for a few minutes, let is infuse into the butter and then remove the sage leaves. Transfer the browned butter to a bowl.
Add a splash of the milk to the brown butter to temper it, reserve the rest of the milk for later.
In a large bowl, add the sugar and eggs and pumpkin. Add in the cooled brown butter and mix well.
Combine the dry ingredients and add to the wet, alternating with splashes of the milk to help combine.
Pour the batter into two parchment lined 8"x5" loaf pans. Bake for 60-70 minutes or until a toothpick comes out clean.
Let them cool, then slice and serve!