Preheat oven to 350F and line 9"-13" pan with parchment paper.

In a medium bowl, sift the flour, baking soda and baking powder. Set aside.

In a large measuring cup, mix together the sour cream and vanilla paste. Set a side.

In a bowl of a standing mixer fitted with the paddle attachment, place the butter and sugar and mix on medium-high until you have a light and fluffy mixture.

Add the eggs, one at a time waiting for each egg to fully incoporate before adding the next. Scrap the bottom and sides of the bowl on occasion. 

Add the flour mix, alternating with the sour cream mix starting and finishing with the flour (total 3 additions for the flour).

After adding the last part of the flour, stop the mixer and using a rubber spatula, mix in any flour strikes.

In a clean mixer bowl, add the heavy whipping cream and whip on high to a soft peak. Gently fold it into the cake batter. 

Evenly spread the batter in the pan and bake for 35-40 minutes, or until a tooth pick comes out clean from the center of the cake.

Remove from oven and allow to completely cool before frosting.