1-First: preheat the oven to 180 °C (350°F) or 160 °C (320°F) for fan ovens, and grease and line two 8-inch cake pans. This step ensures your cake doesn’t stick and bakes uniformly. Sift together the flour, cornstarch, baking soda, baking powder, and salt, then whisk to combine this keeps the batter light.

2-Next: beat the butter, vegetable oil, both sugars, and peanut butter on medium speed for about 3 minutes until creamy. Add the eggs one at a time on low speed, mixing well each time. Then, stir in the vanilla extract and buttermilk until smooth before gently folding in the dry ingredients.

3- Pour the batter evenly into your prepared pans and tap to remove air bubbles. Bake for 30-35 minutes, or until a toothpick comes out clean. Let the cakes cool in the pans for 15-20 minutes, then move to wire racks.

4-For the frosting, mix butter, powdered sugar, vanilla, cream, peanut butter, and salt at low speed for one minute, then beat at medium-high for 10 minutes until fluffy. If needed, adjust the consistency by warming or chilling. Once cooled, frost the layers and assemble it’s that simple!