Preheat the oven to 425 degrees F. Lay out 9 muffin liners in a muffin tin.
Whisk together the flour, cinnamon, baking soda, ginger, nutmeg and salt in a large bowl. Set aside.
In another large bowl, whisk together the pumpkin puree and brown sugar. (For best results, use a stand mixer.) Whisk in both of the eggs, one at a time, until all trace of the egg is gone. Slowly, drizzle in the oil on the side of the bowl while whisking.
Add the dry ingredients, 1/4 cup at a time, then stir the batter thoroughly, until the flour mixture is half gone. Add the yogurt and stir. Add the remaining flour until all visible signs of flour are gone.
Fill a muffin liner about 3/4 full with the batter. Repeat with the remaining 8 liners.
Bake the muffins 10 minutes, then turn down the heat to 375 degrees F and bake until the muffins are browned and a toothpick inserted into the center comes out clean, 10 to 15 more minutes.
Allow the muffins to cool for 10 minutes, then remove them to a cooling rack to cool entirely.