Pan Preparation

1. Put your oven rack in the lower third of the oven. Preheat the oven 350F.
2. Butter the sides and bottom of a 10” round spring form pan. Line the bottom of the pan with parchment paper. *If you don’t have a spring form pan, you can use a 9” cake pan. I prefer the springform pan personally.

Make the streusel topping

1. Combine the sugars, cinnamon, nutmeg and flour in a bowl.
2. Add in the cubes of butter and cut with a pastry blender until you have pea size crumbs.
3. Cover the bowl with plastic wrap and put it in the freezer to chill while you make the buckle batter.

Make the buckle

1. Using a stand mixer fitted with the paddle attachment, cream the butter and sugar on high for 5-7 minutes. You want it to be light and fluffy. Stop every few minutes to scrape down the sides of the bowl.
2. Reduce the speed to low and add in the eggs, one at a time mixing well after each one. Add in the vanilla, yogurt and lemon oil. Mix until thoroughly incorporated.
3. In a separate bowl add the flours, baking powder, salt and cinnamon. Mix well.
4. With the mixer on the lowest speed, slowly add in the dry ingredients. You ONLY want to mix until it’s all incorporated. I actually tend to finish mixing it by hand. You don’t really want air bubbles in this. Using a spatula or spoon gently fold in the blueberries. The batter will be thick, so scrape it into the prepared pan and spread it out evenly.
5. Remove the streusel topping from the freezer and sprinkle it on top of the batter pressing down in gently. Bake for 45-60 minutes or until the streusel is golden brown and firm to the touch and a cake tester, inserted, comes out with a few moist crumbs. Put the pan on a cooling rack.
6. Allow to cool for 15 minutes then gently run a knife around the edges of the pan. Carefully unlatch the spring form pan and lift the cake up and out of the ring. Let the cake remain on the bottom of the pan. Let cool for about an hour.
7. If you have a big spatula, you can separate the buckle from the bottom of the pan. Or I left my parchment round be about a 1/2” bigger than the base of the pan. This way I could just slide my spatula in between the parchment and the cake.

Make the Glaze

1. Once the cake is cooled completely mix the confectioners’ sugar and milk until creamy. I prefer it to have the consistency of maple syrup when I drizzle it.
2. Drizzle over top of the buckle.