Preheat over to 350°℉/ 177℃
Whisk together the flour, cocoa, brown sugar, baking soda and salt, breaking up any lumps of cocoa and sugar
Then mix in the wet ingredients
Pour the batter into the baking dish and bake for about 55 minutes. Check that the cake is fully cooked—if needed, continue baking until a toothpick or cake tester inserted in the center comes out clean and dry.
Take the cake out of the over and let cool
While the cake is cooling make the frosting
Allow the cake to cool completely before frosting. If you’re impatient like us, place it in the fridge for a few minutes to help it along to shorten cooling time, once it’s no longer hot. Then frost and enjoy.