Combine the vinegar and Mirin together in a bowl and add the onions. Add a pinch of salt and keep stirring for a few minutes to evenly pickle all of the Combine the vinegar and Mirin together in a bowl and add the onions. Set aside in the fridge.

Fry the bratwurst according to pack instructions.

Get your hotdog bun ready to go. Squeeze a line of The Mayoneur Mayo in the bottom of the bun. Add the Bratwurst and top with the pickled onions on the side of the Bratwurst and crispy onions on the other. Finally squeeze some Mayoneur Wasabi Mayo over the top to finish.