Cut the brownie in half horizontally.
Line the original baking pan with parchment and place one half of the brownie into the bottom of the pan.
Top with scoops of slightly softened vanilla ice cream. Spread evenly over the brownie.
Top with the other half of the brownie gently pressing it into the ice cream.
Top with scoops of slightly softened raspberry sorbet. Spread evenly over the brownie. Put brownie cake in airtight container and freeze overnight.
Remove from freezer and transfer to a cutting board. Use a knife dipped in hot water to cut the ice cream cake. Run under hot water and wipe clean after every cut for the nicest presentation and ease of cutting.
Cut cake in half. Put one piece back in the freezer while you cut the other. Cut each half into 8 pieces for a total of 16 pieces.
Serve on a tray topped with fresh whipped cream and raspberries. Garnish with fresh mint if desired.