Preheat oven to 350F. Line a 9x5 loaf pan with parchment paper, letting it hang over the sides. Set aside.
Place butter in a small saucepan over medium heat. Melt butter, stirring occasionally until butter is a deep golden brown. Remove from heat and reserve 1/4 cup browned butter in a small bowl and place in refrigerator to chill.
Place remaining 1/4 cup browned butter in a large bowl. whisk pumpkin, yogurt, eggs, sugar, and vanilla until smooth. Whisk in flour, baking soda, baking powder, salt, and pumpkin pie spice until batter is smooth. Scrape batter into prepared pan and gently smooth top.
Bake bread at 350F 45-50 minutes or until a toothpick inserted in middle comes out clean. Cool bread completely, then remove from pan to a cooling rack.