Preheat oven to 350 degrees. Grease and flour a 10-cup capacity bundt pan. Set aside.
Place the butter in a medium skillet (preferably not nonstick or cast iron so that you can more easily see the color change) and heat over medium, swirling the pan frequently. Once the butter has melted, continue to cook, swirly frequently, until the butter has a nutty aroma and is golden brown in color. Immediately transfer to a bowl to cool briefly.
In a large bowl, whisk together flour, baking soda, salt, cinnamon, cardamom, and ginger Set aside.
Combine brown butter, oil, sugar and brown sugar in the work bowl of a stand mixer fitted with the paddle attachment. Mix on medium speed until thoroughly combined, about 2 minutes. Add the eggs one at a time fully incorporating one before adding the next. Add the sour cream and vanilla and mix until fully incorporated and smooth. Add flour mixture and mix on low until just combined. Fold in the pears with a rubber spatula.
Transfer the cake batter into the prepared pan and smooth the top. Bake until a skewer inserted into the middle comes out clean, about 55-60 minutes.
Cool on a wire rack for 15 minutes. Run a knife around the edges of the pan to loosen it from the cake and Invert onto a serving plate. Allow to cool completely. Dust with powdered sugar if desired and serve!