In a saucepan, heat vegetable oil over medium heat. Sauté the chopped shallot until translucent.

Add tarragon and white wine, then reduce mixture by half while stirring. Allow to cool.

Whisk in egg yolks, then incorporate melted butter until thickened.

In a bowl, combine crab meat, mayonnaise, mustard, and lemon zest.

Chill the filling for about 20 minutes.

Shape filling into golf ball-sized croquettes.

Coat each croquette in flour, beaten eggs, then panko breadcrumbs.

Fry croquettes in hot oil until golden brown.

Serve with Béarnaise sauce.