01 - Preheat the oven to 350°F. Grease and flour two 8-inch round cake pans, or line with parchment paper.
02 - In a medium bowl, whisk together flour, baking powder, baking soda, and salt. Set aside.
03 - In a large bowl, beat butter, oil, and granulated sugar until light and fluffy, about 2-3 minutes.
04 - Add eggs one at a time, beating well after each addition. Mix in lemon zest, lemon juice, and vanilla extract.
05 - Add half of the flour mixture to the wet ingredients, mixing just until combined. Pour in the milk and mix. Add the remaining flour mixture and mix until just incorporated.
06 - Gently fold in the blueberries tossed with flour.
07 - Divide the batter evenly between the prepared pans and smooth the tops. Bake for 30-35 minutes, or until a toothpick inserted into the center comes out clean.
08 - Cool in pans for 10 minutes, then turn out onto wire racks to cool completely.
09 - Beat cream cheese and butter together until creamy. Add powdered sugar, lemon juice, lemon zest, vanilla, and salt. Beat until smooth and fluffy.
10 - Once cakes are completely cool, spread a layer of frosting over one layer, top with the second cake, and frost the top and sides.
11 - Garnish with extra blueberries and lemon zest if desired.