Preheat the oven to 180°c. Line a muffin tin with patty pans.
Cream the butter and sugar with an electric mixer on high until it is pale and fluffy. Add the vanilla essence and egg and mix well.
Sift the flour, baking soda and salt together and add to the butter mix. Beat on low until it is all combined.
Add the beer and stir carefully until well combined. The mix will be very runny.
Spoon the batter into the cupcake forms so that all cupcakes have roughly the same amount of batter. Bake for 15-20 minutes until golden and a skewer inserted into the cupcake comes out clean. Remove from the muffin form and allow to cool.
For the beer caramel
Place the sugars and beer in a saucepan and stir over low heat until all of the sugar dissolves. Bring the mixture to a boil then allow to simmer, stirring occasionally, until it thickens. Be careful not to burn the sugar and please be careful - hot sugar burns!
Carefully add the butter, stirring constantly until it has totally melted. Be careful, it might bubble up.
Remove the pan from the heat and add the cream, stirring until it is all combined. Return the pan to the heat and bring to the boil then allow to simmer for approximately one minute. Remove from the heat and allow to cool totally before using.
For the frosting
Cream the sugar until pale and fluffy. Add the icing sugar and mix well.
Add the white chocolate, vanilla essence, salt and cream and mix until well combined. If the frosting is too runny, add some more icing sugar until the right consistency is reached. If it is too thick, add some more cream. Add a little at a time, especially when adding cream, and mix well between additions.
Dip the pretzels in the dark chocolate or drizzle the chocolate over them, whichever is easier. Place them somewhere cool (but not moist) until the chocolate hardens.
Pipe the frosting onto the cupcakes using your preferred method. Drizzle extra beer caramel over the frosting and top with a chocolate-dipped pretzel.
We use unsalted butter in our recipes unless otherwise indicated. If you are using salted butter, taste test before adding any salt.We used Oktoberfest beer, a beer brewed by one of the six Munich breweries specifically for the Oktoberfest. If you can't get Oktoberfest beer (because it is the wrong time of year or you don't live in Germany), use any German-style Helles or a pale larger or pilsner.