Preheat the oven to 350.
In a sauce pan, add the butter, sugar and water and bring to a boil, stirring often. Stir one minute to make sure the sugar melts. Turn off the heat and add the chocolate. Stir until melted and set aside to cool 10 minutes.
Line a 10x15 inch jelly roll pan with parchment paper. Set aside.
Toast the almonds: Heat a dry skillet (no oil) over medium heat two minutes. Add the almonds and stir constantly until you can just smell them and they start to brown a bit. Don't walk away! About 3 or 4 minutes. Turn off the heat and set aside to cool.
In a medium bowl, add the flour, cocoa, baking soda, and salt and stir to combine. Add the egg and mix lightly.
While stirring the flour and egg mixture constantly, slowly pour in the chocolate in a steady stream so the egg doesn't curdle. Add all the chocolate and stir until no pockets of flour are seen.
Transfer the mixture to your pan and spread it as evenly as you can. It's a thick batter so do your best.
Bake on the middle rack until firm in the center about 10-12 minutes.
Remove from the oven and allow to cool to room temperature on a cooling rack. Just lift the parchment paper and all out of the pan.
Once the brownie is cool, set the ice cream out to soften. If yours isn't soft enough, you can microwave it in 30 second intervals, stirring it well until it is.
Cut your brownie in half lengthwise.
Spread each side with one type of ice cream.
Sprinkle on the toasted almonds and sandwich both sides together. Wrap tightly in plastic wrap and freeze until firm. About two hours.
Once hardened, unwrap and slice in to 1-inch thick bars. Wrap each bar in plastic wrap and put them all in a gallon zip lock back to enjoy as needed.