Place the larger basil leaves in a large mortar and pestle, reserving the smaller ones placed in a cup of cold water. Add the anchovy paste and a good pinch of salt into the pestle and mortar into a green paste. Add the juice of one lemon and the olive oil and whisk together with a fork.

Pick through your mussels to find ones that are open and won't close - they're dead, so throw 'em away. You'll find that you won't get the whole crop of mussels, even when they're cooked which is why the recipe is a bit overkill with the 3 and 1/2 lbs. Cook the pasta now until al dente and drain in a colander. While the pasta is cooking, heat up a large saute pan for the mussels. When it's super hot, throw in your mussels and the white wine, covering with a lid. Give it a good shake, and cook for a few minutes until the mussels have opened up. Remove the ones that haven't opened. Toss your pasta into the pan along with the basil oil, stirring it around. Add some more lemon juice and seasoning to taste, and serve right away. Pour over some of the sauce, and sprinkle with the chopped red chillies and the smaller basil leaves drained.