Instructions

1. Put the garlic, most of the watercress, lemon zest, walnuts and cheese into a food processor and whiz to a smooth paste. Slowly drizzle in the olive oil and about a spoonful water to make a thick paste. Season with salt and pepper. Taste, add more lemon juice, if needed. Set aside.
2. Bring some water to the boil and add the gnocchi. When they pop to the surface, transfer them to a mixing bowl, using a slotted spoon. Add the pesto, mix well.
3. Fold in a handful of watercress leaves, then serve with freshly ground pepper and chopped walnut pieces.