Preheat your oven to 350°F (175°C). Grease your two cake pans with butter and dust them with flour. Line the bottoms with parchment paper to ensure easy removal.

Place the room-temperature butter and sugar in your mixer bowl. Beat them on medium-high speed for about five minutes. The mixture should look very pale and fluffy.

Lower the mixer speed and add the eggs one at a time. Make sure each egg is fully mixed before adding the next. This creates a very stable cake structure.

Add the pure vanilla extract and the almond extract to the bowl. The almond extract is Ina’s secret for a deep, professional flavor. Mix briefly until just combined.

In a separate bowl, sift together the flour, baking powder, baking soda, and salt. Sifting is very important to avoid lumps in your delicate cake batter.

Add the dry ingredients and buttermilk to the butter mixture in three parts. Start and end with the flour. Mix on low speed until the batter is just smooth.

Divide the batter evenly between the two prepared pans. Bake for 35 to 40 minutes. A toothpick should come out clean when inserted into the center.

Let the cakes cool in the pans for ten minutes. Then, turn them out onto a wire rack. They must be completely cold before you start the frosting.

Beat the butter, egg yolk, and vanilla for about three minutes. Gradually add the sifted confectioners' sugar on low speed. Increase speed and whip until very smooth.

Place one cake layer on a plate and spread some frosting. Place the second layer on top. Cover the top and sides with the remaining buttercream using a spatula.