Preheat the oven to 350 degrees F.
Add the 8 tablespoons of butter to a large skillet or pot and heat it over medium-low heat. Let the butter begin to bubble and whisk occasionally, until brown bits begin to appear on the bottom. Whisk until the butter is slightly golden, then remove it from the heat. Pour the butter in a bowl to let it cool to room temperature.
Place the remaining 1 tablespoon of butter in a 9x13 inch baking dish and stick the baking dish in the oven for 2 to 3 minutes, so the butter will melt while you make the cake. This is how we grease out pan. You can brush the butter all around the dish once it is melted.
In a small bowl, whisk together the flour, baking soda, cinnamon, nutmeg and salt.
In the bowl of your electric mixer, beat together the cooled brown butter and the sugar until combined. Add in the eggs one at a time, beating until combined. Beat in the vanilla extract.
Add a third of the dry ingredients, then add half of the yogurt. Add another third of the dry ingredients and the remaining yogurt. Finish the with the remaining dry ingredients, mixing until just combined. Stir the pears into the batter with a spatula.
Pour the batter into the buttered dish.
Top with the crumb mixture.
Bake the coffee cake for 4o to 45 minutes, or until a tester inserted into the center comes out clean. Let the coffee cake cool completely before serving!