Preheat your oven to 330 degrees, check for accurate temp with an oven thermometer
In a bowl combine buttermilk, flavored extract of your choice, sour cream if using, and room temp eggs. Mix to break up the eggs and combine.
Add flour, salt, baking powder, and sugar to the bowl of your mixer.
Add the softened butter and mix with your paddle attachment on the lowest setting on your stand mixer until it looks like coarse sand, about 1 minute.
With your mixer on low, add around half of your wet ingredients. You really just want to add enough liquid so that everything is a little wet without forming a dough texture, it should resemble cake batter. Then turn it to medium and let it mix for 2 minutes. Set a timer and do not go over. This helps develop the structure of the cake, without over mixing.
Scrape your bowl after the 2 minutes. With your mixer on low add the rest of your wet ingredients. Mix just until totally combined. About 15 seconds.
Prepare your pans by spraying the sides and lining the bottom with parchment paper.
Divide the batter evenly between 3, 6 inch pans. I like to do about 18 oz per 6 inch pan. There will be a little left over batter, I like to bake a bento cake with it.
Smooth the batter so it’s flat in the pan, then cover with aluminum foil.
Bake until done about 60 min. When the cake is done the sides will start to slightly pull away from the pan and a toothpick inserted in the center will come out clean.
Place on cooling rack, carefully remove foil.
Let the cakes cool for about 15 min or until pans are cool enough to touch and remove them from pans to cool completely.
Once cakes are totally cool I recommend wrapping in plastic wrap and freezing to decorate cake from frozen.****