Cut out three butternut rounds using a three-inch round cutter. Toss in a bowl with the shallots and olive oil and season well.
Melt the butter in a frying pan over a medium heat. Add the rounds and cook for three minutes on each side.
To cook the lamb, place a griddle pan over a high heat.
Season the lamb steak on both sides. Place in the griddle pan and cook for two minutes on each side.
Remove and slice the steak.
To serve, lay the butternut rounds in a pile on a serving plate. Place the sliced lamb on top.