Preheat the oven to 350 degrees F. Grease a 13-inch by 9-inch baking pan with butter. Dust with flour and tap out the excess.

In a medium bowl, sift together the flour, baking powder, baking soda and salt. In the bowl of a stand mixer fitted with the whisk attachment, beat the eggs and sugar until pale and thick, about 4 minutes. Beat in the melted butter followed by the oil and vanilla extract.

With the mixer on low speed, beat in the dry ingredients in 3 additions alternating with the milk in 2 additions until just combined. Be careful not to over mix. Spread the batter into the prepared pan and bake for 35-40 minutes until a toothpick inserted in the center comes out clean. Let the cake cool completely.

For the frosting, place the chocolate chips in a large bowl. In a small saucepan over medium heat, bring the heavy cream and salt to a simmer. Pour over the chocolate chips. Let sit a few minutes before stirring until smooth. Whisk in the vanilla extract. Let the mixture cool to room temperature, stirring occasionally. It should thicken to a spreadable consistency. Use an offset spatula to spread the frosting over the cake.