Clean, wash and cut the leek into rings. Peel onion, cut into rings. Heat oil in a pan, fry leek and onion rings in it. Take them out and let them cool down.
In the meantime clean, wash and spin-dry lamb's lettuce. Drain the corn. Cut chicken sausage into halves. Mix vinegar with mustard. Season with salt, pepper and sugar. Fold in olive oil.
Mix lamb's lettuce, leek, onion rings, corn and poultry sausage and drizzle with salad dressing. Farmers crusty bread goes well with it.