Mix brownie mix according to manufacturer’s instructions. Paper and spray a quarter sheet pan, deposit 2 pounds 8 oz prepared brownie batter and spread to the edges. Bake until set all the way through and let cool completely.
Using a 7-inch silicone saverin mold, measure the outside edge and inside edge of the mold, using ring cutters, cut a ring of brownie that will fit the dimensions of the ring mold without going over the edges. Freeze brownie circle. Lightly treat the mold with pan spray.
In the bowl of a stand mixer fitted with the whip attachment, add 200g mousse mix, 250g whole milk, and 50g cherry icing fruit. Whip until the mixture is thick and resembles fluffy mousse. Pipe into prepared mold. Gently press prepared brownie ring on top, use an offset spatula to smooth the top, freeze overnight.
Bloom 7.5 each gelatin leaves in cold water, remove from water and set in a small bowl.
In a medium pot, bring 10.5oz sugar and 7.35oz heavy cream to a boil over medium heat, stirring until the sugar dissolves.
In a different bowl, slowly mix together 8.6oz cocoa powder and 10.5oz water, whisk until no lumps remain and it is a thick paste.
Remove the pot from the heat, stir the bloomed gelatin into the cream-sugar mixture until dissolved, then stir in the cocoa powder paste until combined, stir in black food coloring
Emulsify the mixture with a hand blender (immersion blender) to remove any lumps, until smooth.
Strain the glaze mixture through a mesh strainer over a heatproof bowl to remove any clumps of undissolved cocoa powder.
Cover and chill in the fridge overnight to set, until ready to use.
Note: to glaze properly, this mixture MUST be melted to between 90F and 95F any colder or hotter and the glaze WILL NOT WORK.
Remove frozen entremet from freezer, unmold, and cut a cardboard ring the same size as the brownie ring. Place cardboard under unmolded entremets and place on a flan ring over an icing grate. Let thaw JUST UNTIL FROST DISAPPEARS- no more, no less. Being careful that glaze is between 90F and 95F and does not have ANY lumps, pour glaze over top of entremet. Use an offset spatula to remove any drips from the bottom, place cocoa nibs around the bottom, and place on service vessel. Place directly into the cooler.
Temper ruby chocolate onto a large sheet of acetate paper. When chocolate is nearly set but still just soft, use a biscuit cutter set to cut various sizes of circles from the chocolate. Reserve chocolate circles. Re-melt the chocolate scraps and drizzle a bit over one side of the entremet. Using a hot pallet knife, make small incisions where the ruby discs will be entered into the top of the entremet. Scatter some crispearls and fresh cherries on top. NOTE: Entremet MUST be served directly from the cooler and must be kept cold.