Preheat your oven to 350°F (175°C). Grease and flour a 9x13 inch baking pan.
In a large mixing bowl, cream together the softened butter and granulated sugar until light and fluffy.
Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.
In a separate bowl, whisk together the flour, baking powder, and salt. Gradually add this dry mixture to the wet mixture, alternating with the milk. Mix until just combined.
Pour the batter into the prepared baking pan and spread it evenly. Bake for 25-30 minutes, or until a toothpick inserted in the center comes out clean.
Allow the cake to cool in the pan for 10 minutes, then transfer it to a wire rack to cool completely.
While the cake is cooling, prepare the whipped cream. In a medium bowl, beat the heavy cream, powdered sugar, and vanilla extract until soft peaks form.
Once the cake is completely cool, spread the whipped cream evenly over the top. Garnish with fresh berries if desired.
Slice and serve. Enjoy your delicious Papal Cream Cake!