Preheat oven to 350°F. Line your baking pan with parchment paper.
Heat some water in a sauce pan. In a mixing bowl on top of the pan, melt together the butter and non-mini chocolate chips. Note: You can do this in a microwave, just run it for 20 seconds at a time and stir to mix in between, until fully melted.
Mix the cocoa powder into your chocolate mixture.
Mix in the sugar, eggs, vanilla, and salt, stirring to combine fully.
Mix in the flour and, again, fully combine.
Stir in the mini chocolate chips, then spread the batter evenly in your baking pan.
Bake for 35 minutes, or until a tester comes out clean.
Remove from oven and allow to cool completely. While cooling, make your cream and ganache.