Melt chocolate. If using candy melts or wafer melts, follow package instructions. If using chocolate chips, melt over a double boiler or glass bowl over a pot with boiling water.
Scoop about 1 tbsp of the melted chocolate into the silicone molds. Using a spoon or pastry brush, spread the chocolate up the sides.
Place silicone mold in the freezer for 10 minutes.
Remove from freezer and add more chocolate to fill-in any spots that look thin or that you missed.
Place molds back in freezer if more chocolate was added.
Remove chocolate from freezer and gently pop out of molds.
Warm up a frying pan and even out the rims of half of the chocolate domes so that they are even.
Place a dollop of melted chocolate on a plate and stick one of the evened out domes on it, open side up.
Set a brownie inside the dome. Note: All this, up until this point, can be prepped ahead of time until you are ready to serve.
Right before serving, place a small scoop of ice cream on top of the brownie. Put a mini Oreo on top of that.
Take the remaining domes and even out the edges on the warm pan. Immediately place them onto the dome that contains the brownie. Hold gently for 10-15 seconds.
Warm fudge sauce and pour over domes at the table. This is the wow factor moment.
Enjoy immediately.