In a food processor blend 300grams of tennis biscuits until they are fine crumbs. Melt the butter in the microwave and combine the two. Press the biscuit mixture into a loose bottom tart tin.
Add the cream to a bowl of a stand mixer fitted with a whisk attachment and whip at medium speed until soft peaks form.
Loosen the caramel treat with a fork in a small mixing bowl and then add it to the fresh cream, reserving ¼ cup for decorating. Beat again until well combined and whipped to stiff peaks.
Roughly chop the rest of the biscuits and cop the balance of the chocolate.
Using a rubber spatula, fold through the rest of the biscuits and chopped chocolate into the whipped caramel cream mixture. Pour the mixture over the biscuit shell. Dot the remainder of the caramel mixture on top of the tart and swirl it through with a skewer.
Cover the tart with tin foil and place the dessert into the freezer, and allow the tart to set for about 4 hours or overnight.
Once the tart has frozen, decorate it with extra fresh whipped cream, chopped peppermint crisp chocolate pieces, and sliced bananas. Slice and serve immediately.