Beat again until you have a very thick mixture.
At this point we can add and mix anything we like in the whipped cream mixture,
such unsweetened cocoa powder (to make chocolate), chocolate chips or pistachios (unsalted and roasted).
Spread evenly the whipped cream mixture over the biscuits.
Lay the rest biscuits (up side up) over the whipped cream.
Be careful to place the top biscuit just above the bottom at the same point and in the same direction to create the sandwiches.
Cover and put the baking pan or food container with the sandwiches in the deep freeze and let it stay 3-4 hours at least.
Usually the sandwiches are much better the next day.