For the whiskey-caramel heat a large pan without fat. Caramelise the sugar in it at medium heat until golden brown. Important: Only stir when everything is liquid. Remove the pan from the stove immediately. Carefully fold in the cream (it may splash!). As the caramel hardens, stir the cream-caramel-mix at low heat until everything is liquid again. Then stir in butter and whiskey. Done!
For the hot chocolate, mix 50 ml milk with starch and sugar. Warm up the remaining milk. Chop the chocolate, add it to the milk and melt it while stirring. When the chocolate has melted, stir in the mixed starch and bring to the boil.
Remove from the heat immediately and pour into glasses.
Whip the cream until stiff and spread it on the chocolate. Drizzle whiskey-caramel over it. Spread salt pretzels on top and dust with cocoa. Serve with straws if necessary.