1-Preheat the oven: Preheat the oven to 350 degrees F (177 degrees C). Grease three 8-inch round cake pans and line with parchment paper rounds, then grease the parchment paper.

2-Beat the butter: Beat the butter until smooth and creamy, then add the granulated sugar and brown sugar, mixing until combined. Add the oil and mix until light and creamy.

3-Add the eggs: Add the eggs one at a time, along with the vanilla extract, mixing until fully incorporated and scraping the bowl as needed.

4-Whisk dry ingredients: In a separate bowl, whisk together the flour, baking powder, baking soda, and salt. Add this dry mixture to the wet ingredients in batches, mixing briefly on low speed. Then, add the buttermilk, lemon zest, and lemon juice, mixing just until combined.

5-Toss the blueberries: Toss the blueberries in 1 tablespoon of flour and gently fold them into the batter, being careful not to over-mix. The batter will be thick.

6-Bake the cake: Divide the batter evenly among the prepared pans and bake for 22 to 26 minutes, or until a toothpick inserted in the center comes out clean. Allow the cakes to cool completely in the pans.

7-Prepare the frosting: For the frosting, beat the cream cheese and butter until smooth. Gradually add the confectioners’ sugar, heavy cream, vanilla extract, and salt on low speed, then increase speed and beat for 3 minutes until light and creamy.

8-Assemble the cake: Trim the tops of the cooled cake layers for evenness. Assemble by spreading frosting on each layer, then cover the top and sides. Optionally, decorate with blueberries, lemon zest, or lemon slices. Refrigerate for at least 45 minutes before slicing.

9-Store leftovers: Store any leftovers tightly covered in the refrigerator for up to 5 days.