Preheat the oven to 325 degrees F.
Spray a standard 12-cup bundt pan with non-stick cooking spray and sprinkle lightly with flour.
Using an electric mixer, cream the butter and sugar together until light and fluffy. Then beat in the eggs and vanilla. Mix the flour, baking powder, baking soda, and salt in a separate bowl.
Turn the mixer on low and slowly add the flour and buttermilk, alternating each, until all incorporated.
Lastly, beat in the lemon zest before turning the mixer off. Use a spoon the stir in half the blueberries.
Pour the batter into the bundt pan and sprinkle the remaining blueberries over the top. Bake for 60-80 minutes or until a toothpick comes out clean with no batter on it. Remove the cake from the oven and allow it to cool for minimum of 25 minutes before flipping out onto a cooling rack. DO NOT try flipping the cake any earlier than 25 minutes, or the cake will stick.
For the Crumble Topping:
Once the cake is cooling on the rack, mix the oat crumble. Add all the ingredients to a small bowl and pinch with your fingers to blend the ingredients and break into small pieces. Sprinkle the mixture over a baking sheet and bake in the heated oven for 5-10 minutes. Cool on the baking sheet before proceeding.
For the Glaze:
For the glaze, whisk the buttermilk and powdered sugar in a small bowl. Drizzle the glaze over the cake and immediately sprinkle the oat crumble over the top of the cake before the glaze dries.
I recently co-hosted a baby shower for one of my dear friends with two other friends of mine. It was brunch themed, so I was really excited to finally make a muffin-style bundt cake. I settled on trying out a blueberry muffin bundt cake recipe with a hint of lemon zest. I found an amazing recipe on A Spicy Perspective and ran with it! It was the perfect dessert for brunch.
The final product was moist, flavorful, and zesty. The buttermilk glaze helped to keep the crumble topping securely on the top of the cake. The number one most important thing to remember when trying this recipe at home is to make sure you're allowing time for the cake to cool in the bundt pan completely before flipping it onto the cooling rack. I had a slight crack in the cake from trying to flip it too soon, but was able to keep it one one piece thanks to the buttermilk glaze holding it all together.