Slice them thinly, and then on a declining heat, fry them for more than half an hour in strong, peppery Greek or Palestinian olive oil. Ledbury's wonderful Handley Organics will sell it to you at a bargain price. The fennel will soften and eventually disintegrate into the oil, helped by the addition of flaked salt.
The garlic is sliced wafer thin. You saw Ray Liotta in Goodfellas slicing garlic in prison with a razor blade; well that’s how thin. To the fennel, you add the garlic at about 30 minutes and give it all another 15 minutes.
Pinenuts are roasted until just golden in a heavy pan; and parmesan cheese is shaved.
Meanwhile, a large pan of salted water comes to a lively boil and the pasta is cooked for the desired time. The Italians love it almost raw: they call it al dente.
Here’s the important part. Drain the pasta but not till it’s dry – keep back some tablespoons of the cooking liquid. Add the pasta to the fennel and mix it very well, coating every strand and mixing the oily slush evenly. Sprinkle pinenuts and cheese. If you have fresh herbs, go ahead: basil, fennel tops, dill, even a touch of tarragon. Season to taste with salt and black pepper.
Note: you should always have fresh herbs. Buy or pluck when abundant, and when perfectly dry freeze them on a tray before putting in a bag for winter. Better than dried by far.