Mix oil, sugar and eggs. Add vanilla, salt, baking soda, baking powder, and flour. Add buttermilk. Pour into two 8 inch greased and floured pans and bake for 35-45 minutes. Cool on a wire rack
Frosting
Cream butter in a stand mixer. Add powdered sugar, cream and vanilla. Beat until smooth. Place one cake layer down on a cake plate. Frost that layer. Add second layer. Frost the entire cake. Use leftover frosting for the trees.
Trees
Run the cones in warm water for a couple of seconds to soften them slightly. Take a sharp knife and cut of 1/3 of the side of the cone. Repeat with 2 more cones. Then take another 2 cones and cut them off half way from the bottom to make them shorter. Then slice them 1/3 off like the other cones, so you will have different heights. Place the cones against the sides of the cake. Alternate them so there will be one tall cone, then one short cone.Tint the leftover frosting green. Place in a piping bag with a star tip. Pipe the frosting on top of the cones by dotting it all over the surfaces starting from the bottom of the cones to the top. Sprinkle the cake and trees with a little powdered sugar.