Spray a 12-inch Bundt pan with Baker's Joy cooking spray. Preheat your oven to 350°.
In a large bowl, whisk together the cake mix, brownie mix, eggs, milk, oil, and vanilla just until smooth, about 2 minutes. Pour into the prepared pan.
Bake at 350 degrees for about 50 minutes. A toothpick inserted in the center of the cake shouldn't be gooey, but it's fine if it's streaked or has moist crumbs. You don't want to overbake!
Let cool in the pan for 10-15 minutes, then invert onto a wire rack.
Cool completely, then glaze.
For ganache glaze - Heat the cream in a glass bowl until hot but not simmering. Add the chocolate chips and salt. Let sit for 60-90 seconds, then stir until smooth and glossy.
Pour the chocolate ganache over the top of the cooled cake and let it drip down the sides of the cake.
Cut into slices and serve, preferrably with ice cream or whipped cream.