Jean Yves Bordier Butter from St Malo
This butter is my favourite ingredient - it's made from very good quality organic milk and is salted with sea salt. Bordier is the only supplier in France that allows each chef to choose the quantity of salt in their butter. For me, I always order 5% salt. My favourite type is the seaweed butter - this comes with three different types of seaweed including sweet seaweed and sea lettuce. I like to serve it as a thin slice on roast sea bass or in a very simple way with warm potatoes.
Jean Denis, head chef of the Lecture Room at Sketch, London