Melt both chocolate slowly over a double boiler or microwave in 30s bursts.
Add melted butter to Chocolate and whisk well.
Add room temperature condensed milk, & Sugar and whisk together.
Add All-Purpose Flour, Baking Powder, Cocoa Powder and fold.
Mix Coffee Powder with Hot Water and add it to the brownie mixture. Make sure the water is hot otherwise the mixture will go lumpy. Add a little at a time. You may or may not need all of the liquid. Judge by the consistency of the batter. It should be thick and Lava like.
Line a 10“ square baking tray with parchment paper. And pre heat oven to 170°C.
Add the crushed biscuits to the base and press down.
Pour the batter on to the base and bake for around 40 minutes.
You can take the brownie out of the oven when it is set almost all around the top surface and the very center 1“ is still jiggly. Then let it cool down at room temperature completely before unmounting. You should not insert a skewer into the brownie-like other cakes, because brownie needs to be a bit wet when it comes out of the oven, otherwise, it won’t be fudgy.