Special equipment: Deep fryer
For the tartar sauce: Fold the mayonnaise, pickles, onions, capers, parsley, lemon juice, Dijon mustard, tarragon and hot sauce together in a bowl. Chill until ready to serve.
For the tempura: Heat a deep fryer filled with vegetable oil to 375 degrees F. Line a sheet pan with paper towels.
Combine the flour, water, yellow mustard, if using, and baking powder in a bowl. Whisk the ingredients together until smooth. Pat the herring fillets dry with some paper towels, then dredge in the batter.
Gently lay the battered herring into the fryer. Cook until it turns a nice golden brown, then lift out of the fryer and lay on the prepared sheet pan to cool. Salt generously with while the fish is still hot.
To serve, toast the brioche buns on a hot griddle or toaster. Dress the buns with the tartar sauce, tomatoes, lettuce and ramps. Add the fish and enjoy!
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.