Barquette sounds fancy but it just means “boat shaped”. This is an easy-make-ahead hors d’ouevre: sear off the lamb and make vegetable garnish the day ahead and assemble just before your guests arrive. Substitute Beligian Endive for the Radicchio di Treviso if you like.
Preheat oven to 450 degrees F.
Season lamb with anise and salt and pepper. Add olive oil to hot sauté pan (with oven proof handles) over high heat. Sear lamb loin on all sides, about 5 minutes. Transfer to oven and cook until medium rare, about 10 minutes. Let rest before slicing. Slice into ¼- inch slices then cut into small pieces. Let cool to room temperature. Refrigerate until ready to assemble hors d’ouevre.
Make vegetable garnish by sauteeing leek, carrot, red pepper and fennel in olive for 2 to 3 minutes in olive oil over medium high heat. Season with salt and pepper. Add garlic and sauté for another 1 minute. Add sherry vinegar and cook until liquid evaporates, about 3 minutes. Let cool to room temperature. Stir in chopped dill. Refrigerate until ready to assemble.
To assemble, place slice of lamb in leaf of radicchio de treviso and top with some of the vegetable garnish. Top with a fennel frond or sprig of dill. Serve at room temperature. Makes 30 cocktail hors d’oeuvres.