Ingredients:

  • 250g all-purpose flour
  • 300g granulated sugar
  • 1 tsp baking soda
  • 0.5 tsp salt
  • 130g creamy peanut butter (for cake)
  • 120ml neutral oil (canola or vegetable)
  • 240ml buttermilk, room temperature
  • 2 large eggs, room temperature
  • 1 tbsp vanilla extract
  • 115g unsalted butter, softened
  • 130g creamy peanut butter (for frosting)
  • 360g powdered sugar, sifted
  • 50ml heavy cream
  • 1 pinch salt

Instructions:

  1. Preheat your oven to 350°F (175°C) and grease your 9x13 pan.
  2. In a large bowl, whisk together the 120ml oil and 130g peanut butter until completely smooth.
  3. Add the 240ml room temperature buttermilk, 2 large eggs, and 1 tbsp vanilla extract to the peanut butter mixture. Whisk vigorously until the color is uniform and no streaks of egg remain.
  4. Sift the 250g flour, 300g sugar, 1 tsp baking soda, and 0.5 tsp salt directly into the wet ingredients. Use a spatula to fold the mixture together. Stop the moment you see no more white flour streaks to keep the crumb tender.
  5. Pour the batter into the prepared pan and smooth the top. Bake for 35 minutes until a toothpick inserted into the center comes out with just a few moist crumbs. If the toothpick is wet, give it 3 more minutes.
  6. While the cake cools completely (do not frost a warm cake!), beat the 115g softened butter and 130g peanut butter for 3 full minutes.
  7. Slowly add the 360g sifted powdered sugar and 50ml heavy cream. Whip on high until the frosting looks pale, fluffy, and voluminous.