Preheat over to 325 degrees
Line a half sheet (13x18) ridged baking sheet with parchment paper. This is absolutely required for the brownie brittle with bake to the sheet and you won't be able to cut it or remove it!
In a microwave safe bowl, melt the chocolate and butter (consider lowering microwave power to 50% and checking every 30 seconds to avoid burning chocolate)
Add vegetable oil to butter/chocolate and stir
Mix cocoa powder into the butter/chocolate and mix thoroughly with a wisk or fork
In a separate mixing bowl, separate egg whites and beat with a mixer until light and fluffy
Add vanilla and sugar to egg whites and beat until thoroughly combined
Pour butter/chocolate mix into egg white mixture and combine thoroughly.
Add flour, salt, and baking soda to egg white mixture. Fold with spatula to combine.
Spread mixture as thin as possible (without showing the sheet beneath) on the lined baking sheet
Sprinkle mini chocolate chips on top.
Bak for 20 minutes (more if you would like crunchy brittle)
Score with a knife when hot to allow for breaking
Let cool completely (approx 20-30 minutes)