Preheat oven to 375 degrees F.
In a large bowl, mix the lemon zest, softened unsalted butter and softened cream cheese until smooth.
Add the sugar, buttermilk, eggs, and vanilla extract to the butter mixture and mix until well combined.
Add the flour, salt, baking soda, and baking powder and mix.
Fold in 1/2 cup of blueberries. Pour the batter into a buttered 9-inch baking pan and smooth the top. Add the remaining blueberries to the top and press the blueberries down a bit.
Bake for 37 minutes or until fully cooked through.
Let the coffee cake come to room temperature, garnish with powdered sugar and enjoy!