Trim both ends off two zucchinis. Grate the zucchini using the largest hole of a box grater to form long ribbons. You can also use a vegetable spiralizer.
Cook zucchini noodles in boiling water for about 1 minute. It should be tender but still firm. Drain and set aside.
Chop the sardines as well and reserve the olive oil from the can.
Heat a sauté pan or a skillet over low heat, then add the olive oil from the can of sardines. Sauté garlic and add the tomatoes, onion, chili, olives, lemon zest, chopped sardines, and oregano or basil. Add a bit more olive oil on the pan if it gets too dry.
Stir to combine the ingredients. Season lightly with pepper, salt, and lemon juice if necessary.
Toss the cooked pasta in the skillet with the sardines and the greens. Add the tomato sauce and toss to coat the pasta evenly.
Once evenly coated, transfer to the serving dish.
Garnish the food with more parsley, pepper flakes or fresh basil if desired.