Ficelle picarde is a dish of Picardy, northern France, consisting of a savory crêpe stuffed with Gruyère cheese, mushrooms, and ham.
Though now considered a classic Picardy dish, its origins appear based in l'hôtel du Commerce, in Amiens-France, where chef, Marcel Lefèvre, created it in 1950 during a local fair. Some stories also state the dish originated in the era of Louis XIV.
Over medium-high heat, brown mushrooms in a little olive oil until the juice disappears.
Add the crême fraiche and a squeeze of lemon juice, salt and pepper. Simmer 10 minutes over low heat.
Remove from heat and let cool until warm.
Place a crêpe flat on a plate, place a slice of ham in the center, then on top-center of ham, lengthwise, a 1/6 portion of the mushroom garniture. Roll the crêpe.
Build and roll for the rest of crêpes and place in a buttered rectangular gratin baking dish.
Sprinkle crêpes with a generous portion of grated Gruyère and bake at 400 °F for 10 minutes until cheese is golden brown.