Preheat your oven to 350°F. Grease and flour a bundt pan thoroughly to prevent sticking. (I like to use Baker’s Joy to grease the pan!)
In a medium bowl, whisk together 3 cups of flour, baking powder, baking soda, and salt. Set aside.
In a separate bowl, toss the blueberries with 2 tablespoons of flour. This helps prevent them from sinking to the bottom of the cake.
In a large mixing bowl, cream the softened butter and sugar until light and fluffy, about 3-4 minutes.
Add eggs one at a time, beating well after each addition. Mix in the lemon juice, lemon zest, sour cream and vanilla extract.
This step is optional: If desired, add a few drops of yellow food coloring to achieve a vibrant lemon color and make sure to mix well. You must add the food coloring at this point and not at the end after the batter is mixed because it will become too dense.
Gradually add the flour mixture to the creamed mixture, Do not overmix.
Next, gently fold in the flour-coated blueberries.
Pour the batter into the prepared bundt pan and smooth the top with a spatula.
Bake in the preheated oven for 1 hour or until a toothpick inserted into the center of the cake comes out clean.
Let the cake cool in the pan for 10 minutes before inverting it onto a wire rack to cool completely.
In a bowl, combine melted butter, powdered sugar, lemon juice, heavy cream, and lemon zest. Whisk until smooth. Adjust the consistency with more lemon juice or powdered sugar, if necessary.
Once the cake is completely cooled, drizzle the icing over the cake. Allow the icing to set before serving. Add lemon slices, fresh blueberries and mint leaves to the top of the cake to decorate.
*This cake is almost the texture of a loaf cake so make sure to cook it PLENTY long enough. If you get to 1 hour and insert a knife ALL THE WAY THROUGH from the bottom to the top and it's not set, cover with foil and keep baking for about 15-20 minutes or entirely set!
*adjust lemon zest to taste - If you prefer more lemon flavor you can add an additional tsp of lemon zest to the batter.