Chop whole milk chocolate. Melt with the butter over a warm water bath. Grind the cornflakes in a universal chopper. Mix the chocolate-butter mixture and the cornflakes well, press them into an oiled rectangular tart tin (20 x 28 cm) as a base and rim.
Chill for about 30 minutes.
Soak gelatine in cold water. Mix cream cheese, peanut cream and caramel spread. Dissolve gelatine. Stir in 5 tablespoons of the cream cheese mixture, stir into the remaining cream cheese. Whip 100 g cream until stiff.
Carefully fold into the cream cheese. Spread the cream on the crumb base, chill for about 1 hour.
Chop dark chocolate. Heat 50 g cream in a small pot, melt chocolate in it while stirring. Let it cool down for about 10 minutes. Carefully remove the tarte from the mould and place it on a plate.
Spread chocolate icing on it and cover with pretzels. Chill the tarte for about 30 minutes.