Coat a 9x13 inch baking dish with cooking spray and set aside. (Or you can use a 9 inch springform pan as I did in the photos.)
In a small bowl, combine the yogurt and baking soda. Set aside.
In a medium bowl, whisk together the flour, baking powder and salt. Set aside.
In the bowl of an electric mixer, cream the butter, coconut oil and sugar until fluffy. Add the eggs one at a time until thoroughly combined. Add the dry ingredients to the batter alternatively with the yogurt mixture until well combined. Stir in the vanilla.
Pour the batter into the baking dish and top with the sliced pears. Whisk together the nuts, sugar and cinnamon and sprinkle over the top of the cake. Bake for 40 -45 minutes or until a toothpick inserted into the center of the cake comes out clean. Let cool for 20 minutes before serving.
Notes
Cake can be made up to 24 hours in advance and stored, covered, at room temperature.