Preheat the oven to 350 degrees F, grease and line a loaf pan*. In a medium bowl combine the flour, cocoa powder, baking soda, and salt. Whisk to combine. Set aside.
In a large bowl combine the oil, sugar, egg, and vanilla. Whisk to combine until light and creamy, 2-3 minutes. Slowly mix in milk.
Add the dry ingredients into the wet ingredients, mix well until completely combined, careful not to overmix. Transfer batter into the prepared loaf pan. Bake at 350 for 45-50 minutes or until a toothpick inserted comes out clean. Allow to cool completely before frosting.
For the cream cheese frosting:
In the bowl of a stand mixer fitted with the paddle attachment or using an electric hand mixer, beat the cream cheese until light and fluffy, 3-4 minutes. Add in the powdered sugar, one cup at a time. Mix thoroughly each time. Add in the vanilla extract and mix until smooth.
Frost cooled cake and top with chocolate curls or a chocolate chunk. Or serve slices unfrosted topped with a dollop of frosting!
Notes
*See image above, I always recommend greasing and lining your loaf pan even if it is non-stick. The parchment makes it easy to lift out of the pan.