This Apple Coffee Cake with Crumb Topping is the perfect fall breakfast or dessert -- Greek yogurt makes it so moist and it's loaded with apples and the best crunchy brown sugar streusel!
Preheat oven to 350 degrees F and lightly grease a 9" Springform pan. Set aside.
In a large bowl, combine oil and brown sugar with a whisk until combined. Add yogurt, eggs and vanilla and whisk until smooth.
Add cinnamon, baking powder, baking soda and salt and stir until combined. Then add flour and stir just until moistened. Stir in apples and spread into prepared pan.
To make the streusel, stir together butter, flour, brown sugar and cinnamon until a crumbly dough forms. Sprinkle over top the cake batter (see notes above for how to get nice, big clusters!).
Bake for 60-70 minutes, or until a toothpick inserted in the middle comes out clean. If the top is browning too quickly, simply cover with a piece of tin foil for the remaining bake time.
To make the glaze, stir together the powdered sugar, maple syrup and melted butter. If needed, add in a bit of milk until desired consistency is reached. Drizzle over cake before serving.
Cake can be stored at room temperature for up to 24 hours, or in the refrigerator up to 5 days. It also freezes perfectly, up to 3 months.