Cook the pasta in salted water following the instructions on the packaging.
In the meantime, dry-fry the pine nuts for about 2 minutes in a pan until golden then set aside.
Heat the oil in the pan, soften the onion , then add the garlic. Stir for a minute, then add the spinach & raisins and cook for 2-3 minutes. When the spinach is wilted, add the lemon zest and juice.
Drain the pasta, then add it to the spinach mixture. Heat it through, while constantly stirring. You can add some of the cooking water to make it more moist.
Serve the pasta on two plates and crumble some feta on the top to your liking.