In a large bowl, cream sugar and shortening. Add egg and vanilla; beat well.
In a medium bowl, combine dry ingredients. Add alternately with milk to the creamed mixture.
Spread in a greased 9” square baking pan. Bake at 350°F for 20–25 minutes.
Cool on a wire rack.
In a large bowl, add heavy cream, sugar, and vanilla. Using a mixer, beat until soft peaks form, about 1½ to 2 minutes. Add whipped topping, pudding, and milk. Stir until mixed.
Cut the cake into nine servings. Split each serving horizontally and fill with whipped cream and strawberries. Replace the top of the cake; garnish with more berries and a dollop of whipped cream. Serve immediately.