Remove spinach to a bowl of ice water to stop the cooking process. Drain the spinach then squeeze out as much excess water as possible.

In the bowl of a food processor (fitted with a blade attachment) add the spinach, ricotta, eggs, Parmesan and nutmeg. Pulse until well combined. Slowly add the flour in batches, blending after each, until a dough forms. Season with salt and pepper.

On a clean, lightly floured workspace turn gnudi dough out and shape into a rectangle.

Use a tablespoon to measure rounded scoops (about 20g each). Dust with a bit of flour and roll into even balls. Set aside on a floured baking sheet and continue with the remaining dough. You should end up with about 30 gnudi.

Bring a large pot of water to a boil over medium-high heat. Add the gnudi and boil until tender and cooked through, about 3 minutes. Drain and set aside.

Heat a large sauté pan over medium-low heat, add the butter and allow to melt. Continue to cook the butter, swirling it around the pan occasionally, until the foam subsides, about 2 minutes. Remove the pan from heat and stir in the lemon juice and lemon zest.

Add the gnudi to the pan and gently turn to coat in the butter sauce. Divide among warmed plates and top with chopped herbs. Serve immediately.