Preheat your oven to 375 degrees F and line the bottom of a 9-inch cake pan with parchment paper.
Add 1 1/2 cups of semi-sweet chocolate chips and butter to a heat-proof bowl and microwave in 30-second intervals, stirring in between, until the butter and chocolate are completely smooth.
Allow the chocolate-butter mixture to cool for 4-5 minutes then whisk in the sugar.
Add the eggs one at a time, and whisk each egg fully before adding the next.
Add the vanilla extract, salt, and unsweetened cocoa powder, and mix until well combined.
Pour the mixture into the prepared cake pan and smooth out the top with a rubber spatula. Bake for 30-32 minutes.
Allow the cake to cool completely.
To make the chocolate ganache, add 1/2 cup of semi-sweet chocolate chips to a medium heat-proof bowl.
Add heavy cream to a small saucepan and heat until it comes to a simmer. Pour the heavy cream over the chocolate chips and let it sit for 5 minutes.
Once the 5 minutes are up, whisk the chocolate chips and heavy cream until it becomes smooth and a bit thick. This should take 1-2 minutes.
Pour the chocolate ganache all over the chocolate cake and smooth out the top. Let it sit for 2-3 hours or until the chocolate ganache sets.
Once the chocolate ganache sets, garnish with fresh raspberries and blueberries. Top lightly with cocoa powder, if desired, and enjoy!