For the cake

1. Preheat the oven to 350°F. Generously grease and flour a 12-cup bundt pan.
2. Toss the rinsed blueberries with 1 tablespoon of flour in a small bowl until they are evenly coated. Set them aside.
3. Whisk together the remaining 3 cups of flour, baking powder, and salt in a medium or large bowl and set the bowl aside.
4. Combine the sugar, brown sugar, and butter in the mixing bowl of a stand mixer; cream the butter and sugars together until very light and fluffy, this will take several minutes.
5. Add the eggs, one at a time, beating each egg completely into the butter and sugar before adding the next.  Next, add the vanilla, lemon juice, and lemon zest and continue mixing until everything is just combined.
6. Alternately adding the dry ingredients and sour cream, ⅓ of each at a time, mixing at low speed until the batter is just mixed and thick. Be careful not to overmix the batter. Fold blueberries into batter until they are evenly distributed.
7. Bake the cake for 55-65 minutes. Set on a cooling rack for twenty minutes. Allow the bundt cake to cool in the pan for 15-20 minutes (don’t let it cool completely, or it’ll get stuck), then turn out onto a cooling rack or plate to finish cooling.

For the glaze

1. Combine the melted butter with the powdered sugar, lemon zest and juice and start whisking together. Add the milk, 1 teaspoon at a time to thin the glaze as needed until you reach the desired consistency. You want the glaze to run off your spoon but still be thick enough for the slow drip. Pour over the cooled cake.