Squeeze a lemon into a bowl. Clean the anchovies; remove head and insides, bone them and rinse them in cold water, once drained, dry them in a clean towel. Arrange them in a deep dish, season with salt and chilli and sprinkle them with the lemon juice.Marinate them for 2 hours; after about an hour sprinkle them with 2 tbsp of olive oil remove the tougher leaves and the core from the Swiss chard and lice the tender leaves into strips then rinse them in cold water.Put them in a pan with the left over oil and garlic; pour vinegar and water enough to cover; then add salt and pepper. Bring to the boil over a gentle heat, cover with a lid and simmer for 20 minutes over a medium heat, mixing from time to time.Two minutes before it is ready add the drained anchovies and mix well. In the meanwhile cook the pasta in plenty of boiling salted water, drain it al dente and dress it with the sauce.