Preheat oven to 325F degrees. Spray bundt pan (REALLY WELL) with nonstick baking spray (I like the kind that has flour in it - like Baker's Joy).
Using an electric mixer, cream together the butter and sugar. It should look nice and fluffy when combined.
Then beat in eggs, vanilla extract and lemon extract into the sugar/butter mixture.
Next, in a separate bowl, combine flour, baking powder, baking soda and salt. Stir together with a fork until combined.
At this point, you are going to alternately add in the flour mixture and buttermilk to the sugar/butter mixture.
Add a little flour, then a little buttermilk, a little more flour and a little more buttermilk...until it's all incorporated. Don't overmix.
If you have a stand mixer, be sure to occasionally scrape down the sides of the bowl. Gently stir in HALF of the blueberries. Be very careful when stirring so you don't bust open all the berries. Just gently fold them in.
Now add the batter into the bundt pan. Then add the rest of the blueberries on top.
Bake for about 65-75 minutes. Oven times vary but the top should be golden brown and a inserted toothpick should come out with no batter on it.
Allow the cake to cool COMPLETELY before releasing (about an hour and half or so.)
While the cake is cooling, make crumble topping. Combine all ingredients in a small bowl using a fork or your fingers. Mix until crumbly.
Then spread mixture into a small baking pan and bake in 325F degree oven for about 8 minutes. Then take it out of oven and allow it to cool completely.
Once cake has been allowed to cool completely, you can release the cake from the bundt pan. This is the key to getting the cake to come out clean. The pan needs to be totally cooled, then it should release easily.
Start making the glaze. Combine powdered sugar, lemon extract and milk. Stir well. Whisk together until smooth.
Drizzle glaze over cake. Immediately sprinkle on crumble topping so that it sticks to the glaze.
Video
Notes
Please refer to my FAQ’s and ingredient list above for other substitutions or for the answers to the most common questions.
I like the concentrated lemon flavor in lemon extract but you can use lemon juice or lemon zest as well. We just want that hint of lemon flavor in this cake.
Make sure when measuring flour that you do not pack your measuring cup. Just dip your cup into flour and scoop off the excess with your hand or a butter knife. Packing the cup will give you too much flour and make a dense, dry cake.