Preheat oven to 350 degrees. Grease an 8 inch cake pan or springform pan well.
Mix together flour, baking powder, and salt. Toss dry ingredients with berries and lemon zest (this keeps them from sinking to the bottom of the cake.)
Mix together the eggs, oil, vanilla, and juice until well incorporated. Stir into dry ingredients until just combined.
Spread batter into prepared pan and bake for 30-35 minutes or until a toothpick inserted in center comes out clean.
Cool in the pan on a baking rack for 15 minutes. Then remove from pan and cool completely.
While cake is cooling, make the glaze by sifting powdered sugar into a bowl and adding the lemon juice to it. Stir until a thin glaze is reached (you may need to add a dash of water or a bit more powdered sugar depending on how juicy your lemon is).
Pour the glaze over the cake.
I use a mixture of whole wheat flour and white wheat flour for this healthier coffee cake recipe. You can use all-purpose flour as well. If you want this to be 100% whole wheat, I recommend using a whole wheat pastry flour.
Grape juice is my secret to keeping this cake sweet and dare I say, moist. You can use any 100% berry blend juice you like. If you are afraid your juice will make your cake look dark or purplish, use 100% white grape juice.
Any mixture of berries work in berry coffee cake. Even frozen berries work. If you choose to use frozen berries, either mix them into your flour completely frozen or if you defrost them first, drain off excess liquid.
This cake can be stored at room temperature for 24-36 hours. After that, it will keep in the fridge for up to 5 days.
It is best to not glaze the cake with the optional lemon glaze, until right before serving.