In a large mixing bowl, combine dry ingredients for the base batter (flour, sugar, baking powder, salt).
In a second mixing bowl, combine the eggs and vegetable oil.
Add the wet mix to the dry mix, stirring constantly until smooth.
Preheat oven to 350˚F (180˚C).
Add the milk, and vanilla extract, stir until evenly mixed and the consistency is a thick liquid.
Evenly divide the batter into two separate bowls. Add the cocoa powder to the first bowl. Mix thoroughly.
Add the raspberry jam to other. Mix thoroughly.
In a greased 9-inch (23 cm) cake pan, alternate batters by placing ¼ cup (60 ml) of batter in the center and letting it spread out slightly before adding the other batter (similar to making pancakes). Continue this process until the batter is used up and the pan is full of alternating rings.
Bake cake in a preheated oven for 25-35 minutes or until a wooden toothpick inserted into the center of the cake comes out clean.
While the cake is baking, to make the ganache; in a medium pot set over low heat, mix together heavy cream and chocolate until chocolate has melted and mixture is smooth.
Let mix rest until consistency is thick and mix is cooled.
Cool cake slightly, and then invert onto a wire rack to cool completely.
Pour ganache over the baked and cooled cake starting in the middle and circling towards the edges coating it all.
Once ganache is cooled on cake, garnish with fresh raspberries and powdered sugar.