Cook the spaghetti in boiling salted water according to the packet instructions, then drain. While the pasta is cooking, heat 2 tablespoons of the oil over a high heat in a wide, deep pan with a lid. Add the shallots and chilli to the pan and fry for 2 minutes, stirring, then add the garlic and fry for 10 seconds. Tip in the clams and stir everything together. Pour in the wine and bring to the boil for 2 minutes, then cover with the lid and boil for 2–3 minutes until all the clams have opened (discard any that don’t open). Add the drained pasta to the clams, season well with salt and pepper and toss together. Stir through the lemon juice and parsley and drizzle over the remaining oil. Serve the clams at once while piping hot, spooning over the cooking liquor at the end. Don’t forget to put out extra bowls for the discarded shells.