Bring a large pot of salted water to a boil, then reduce heat so that it’s a rolling rather than a vigorous boil.

Cook the gnocchi in three or four batches, for about 3 to 4 minutes each batch. The gnocchi are done when they float up to the top. Remove each batch with a slotted spoon and transfer to a baking sheet, spreading them out.

Melt butter in a large frying pan. Add garlic, walnuts and sage leaves. Cook, stirring occasionally, until the butter smells nutty and starts to brown.

Add a couple of tablespoons of pasta water and the gnocchi. Gently stir to coat the gnocchi in sauce, adding more water as necessary.

Ladle into four bowls, sprinkle with parsley and Parmesan, and serve immediately.