Move both of your racks into the center of your oven. Preheat the oven to 350°.
In a large bowl, beat the butter and sugar until smooth. Add the egg, extracts, lemon zest, milk and sour cream and blend until smooth.

Add the dry ingredients to the bowl and beat slowly just until well combined and only a few lumps remain.

In a medium bowl, toss the blueberries with 2 Tablespoons flour. Gently fold the floured blueberries into the cake batter.

Prepare three 9" round cake pans by coating them in butter. Scoop 1/4 c. flour into one of the pans and shake around the pan so all of the butter is coated in flour. Dump the excess flour into the next buttered pan and repeat until all pans are buttered and floured.

Scoop 2 cups of batter into each of the floured pans.

Place all of the pans in the oven and bake at 350° for 25-30 minutes, or until the edges are just lightly golden and a toothpick inserted in the center comes out clean.

Allow cake to cool to room temperature.

Meanwhile, in a large bowl, beat the butter and cream cheese until smooth and fluffy. Add the vanilla and almond extracts and mix until smooth.

Add the powdered sugar 1-2 cups at a time, mixing well between each addition until it reaches your desired sweetness.

Using a butter knife, cut around the edges of the cooled cakes to release the white cake from the pan.

Place your hand over the cake and invert the pan.

Very gently allow the cake to release from the pan into your hand. Do not try to rush the process or the cake will break. If it isn't coming free from the pan, use the butter knife to work around the edges of the pan pushing gently in towards the center to release the bottom edges and repeat the process.

If the cake is mounded in the center, use a long bread knife to carefully cut the top off the center so they are flat.

Spread a thin layer of plain buttercream in the very center of your cake stand. Top with one cake layer. Spread a thick layer of frosting over the first layer. Top with another layer of cake and repeat until the three layers are layered with frosting.

Frost the outside of the cake with a thin layer of frosting for a crumb coat. Allow to set for 10 minutes.

Finish the cake with an even thick layer of frosting. Top with optional lemon slices and blueberries.

Serve and enjoy within 24 hours!