Clean and thinly slice the zucchini and finely chop the onion. In a large skillet, heat the oil over medium heat. Add the onion and cook until it is translucent, then add the zucchini. Cook over medium heat, stirring regularly, until the zucchini is golden brown. Set aside. In a separate skillet, heat a few tablespoons of olive oil and add the garlic. After about a minute, add the peeled and cleaned shrimp. Cook until slightly golden and most of the liquid has evaporated.
Season with salt, black pepper and finish cooking for another minute. Add the shrimp to the skillet with the zucchini.
Bring a large pot of water to boil and add 2 tablespoons of sea salt. Cook the pasta until al dente, drain it, and add it to the skillet with the zucchini and shrimp. Toss to mix well over medium heat.