Pasta alle Vongole

Heat a large frying pan over medium-high heat and add a tablespoon of oil. Add the onion, parsley stems, and as many small clams as fit in a single layer. Pour over 175 ml wine and increase the heat to high. Cover and steam for 3-4 minutes until the clams open. Remove the clams as they open and transfer to a bowl. Repeat with the remaining clams and wine.

Strain the cooking liquid through a fine sieve and set aside. When the clams are cool enough to handle, remove them from the shells and chop roughly. Set the chopped clams aside in a small bowl with enough cooking liquid to cover them. Discard the shells.

Wipe the pan clean and set over medium heat. Add oil and the finely chopped onion with a pinch of salt. Cook until soft, about 12 minutes. Meanwhile, cook the pasta until nearly al dente.

Add the garlic and pepper flakes to the onion and let them sizzle gently. Add the Manila clams and cook until they begin to open. Add some of the reserved cooking liquid or white wine and cover the pan. When the clams open, add the chopped small clams. Season with lemon juice to taste.

Drain the pasta, reserving 225 ml of the cooking water. Add the pasta to the clams and simmer until it absorbs the sauce. Stir in the butter and grated Parmesan, tossing well.

Serve immediately with crusty bread to soak up the sauce.