Lovely subtle flavours! Can't be made until Jerusalem artichokes are available in the shops. These quantities make enough for a first course for 6 people. Have a hot oven ready for the initial roasting of veg.
Toss the Jerusalem artichokes and butternut squash in about 2 teaspoons of olive oil and place in a roasting tin. Roast in the oven till browned and tender.
Bring a pan of water to the boil. Add the green beans and blanch till tender but still crisp, 2 to 3 minutes. Remove the beans from the pan of boiling water and immediately place in a bath of ice water to stop the cooking process. Set aside.
Add the new potatoes to the pan of boiling water from the beans, topping up with hot water from the kettle if needed. Boil gently till tender, about 10 minutes.
Meanile, heat a ribbed griddle pan until very hot. When the potatoes are cooked, peel and slice them. Rub a little oil on the cut surfaces and char-grill.
Just before serving, toss the cooked vegetables, olives and tomatoes in the Parmesan. Arrange on a plate and season to taste. Drizzle with truffle oil and vinegar. Top with quartered eggs and a sprinkling of lemon juice.