Put a pot of water on to boil.
In a large skillet over medium-high heat, add 2 tbsp of olive oil, until hot, then add the shallot and cook until softened, about 5 to 8 minutes. Reduce the heat as necessary to keep the shallots from browning. Next, add the shredded zucchini, and season with the salt and pepper. Continue cooking, stirring occasionally, until the zucchini is rather soft, about 10 minutes, and then turn off the heat.
Meanwhile, use a mortar and pestle to pound garlic, basil, and a pinch of salt into a rough paste, or use a mini food processor. Stir in 3 tablespoons of olive oil.
Salt the pasta water well and put in the pasta, stirring. Boil according to the package's instructions, but make sure to keep the pasta quite al dente. Drain pasta, reserving 1 cup of cooking water.
Add the cooked pasta to the zucchini in the skillet and turn the heat to medium-high. Add ½ cup cooking water, then the ricotta, nutritional yeast, crushed red pepper, and lemon zest, stirring to distribute. Check seasoning and adjust. Cook for 1 minute more. The Mixture should look creamy. Add a little more pasta water if necessary.
Finally, add the basil paste and quickly stir to incorporate. Spoon pasta into warm soup plates and serve immediately.
Store leftovers in the fridge for up to 3 days