Using paper towels or a clean kitchen towel, squeeze the excess moisture out of the shredded zucchini. Set it aside. Fill a large stock pot with water for the pasta and set it to boil. Cook the pasta according to the directions on the box. Drain it and set it aside.
While the pasta is cooking, heat the coconut oil in a large pan over medium-low heat. Add the onions and a pinch of salt and let them cook for about 15-20 minutes until they start to caramelize and turn golden brown. Add the garlic, shredded zucchini, and a pinch more of salt and pepper to the pan. Cook for 8-10 minutes or until the zucchini has softened. Add the nutritional yeast, the lemon zest and juice, and the cooked pasta to the zucchini mixture and cook for another 1-2 minutes. Taste the mixture and add more salt and pepper as needed. Remove the pan from the heat and stir in the tarragon. Top each serving with toasted almonds and a sprinkle of fresh tarragon if you like.