Preheat oven to 375°.
Lightly grease and line bottom with parchment paper one 9 inch cake pan.
In a microwave safe bowl, place chocolate chips and butter.
Place bowl in microwave and cook for 30 seconds, remove from microwave and stir.
Return to microwave and cook at 20 second intervals, stirring after each 20 seconds until almost smooth (mostly smooth but still a little lumpy), then stir until smooth.
Add sugar, cocoa powder and vanilla.
Stir just until combined.
Add eggs and using a mixer beat together until just combined.
Bake for 23-25 minutes.
Let cool in pan for 5 minutes.
Flip cake on serving plate or cake stand and cover with Ganache.
Chef's notes: Either Ganache recipe will work well, but the Ganache II is just about the right amount for this cake.