Tarragon Perch with Asparagus

Peel the asparagus and trim off the woody bottom ends. Juice and zest the lemon. Cook the asparagus in simmering salted water seasoned with the half of the lemon juice, half of the zest and the sugar for 25 minutes. Reserve some broth. 

Preheat the oven to 180°C (approximately 350°F).

Rinse the fish fillets and pat dry. Season with salt and pepper. Heat the oil in a pan and saute the fish skin-side down for 1-2 minutes.  Transfer the fish, skin-side down to a parchment-lined baking sheet.

Mince or crush the bread into breadcrumbs and toast in a dry pan. Rinse the tarragon, shake dry, pluck the leaves and chop finely. Separate the egg. Melt the butter. Beat the egg whites until stiff. Combine the bread crumbs with 3/4 of tarragon, butter, remaining lemon juice and egg yolks. Season with salt and pepper. Fold in the egg white and spread the mixture evenly on the fish fillets. Bake until golden, about 20 minutes.