Preheat oven to 350. Butter and flour a 8x8 baking dish and set aside.
In a bowl combine all ingredients to crumble topping and set aside. In a large mixer or in a bowl using hand mixer cream butter and sugar from wet ingredients until well combined and add eggs, vanilla, maple syrup and yogurt and mix until well incorporated.
Combine pears, orange zest and juice in a separate bowl and add to wet ingredients. Mix together until combined. In a separate bowl combine dry ingredients and add to wet ingredients. Mix together until incorporated. **Do not over mix!**
Spread half wet mixture in pan and sprinkle crumble topping evenly over the top. Then spread the rest of the wet mixture over top and sprinkle the rest of the crumble topping. Bake for 45 minutes or until toothpick comes out clean.