Soak the soy curls in hot water for 8 to 10 minutes. Drain and thoroughly squeeze out the excess water through a fine-mesh sieve or cheesecloth.
Meanwhile, cook the pasta. Bring a large pot of salted water to a boil over medium-high heat. Cook the fettuccine according to the package directions until al dente. Before draining, reserve 1 cup of the starchy cooking water. Drain the pasta, but do not rinse.
To make the sauce, drain and rinse the cashews and place them in a high-powered blender along with the milk, nutritional yeast, garlic, and Cajun seasoning. Blend until very smooth. Set aside.
Pour the salt and spices for the blackened chick’n into a large bowl. Using a fork or whisk, mix the seasonings well. Toss the soy curls in with the seasonings and coat generously using your hands.
To cook the vegetables, heat the olive oil in a sauté pan over high heat. You’ll know the oil is hot enough when it is shimmering and slides easily around the bottom of the pan. When the oil is hot, carefully add the tomatoes and cook for 1 minute without disturbing. Stir gently and cook until the tomatoes begin to blister, 2 to 3 more minutes.
Add the bell peppers and sauté until they’re softened, 5 to 7 minutes. Carefully remove the tomatoes and peppers from the pan with a slotted spoon and lower the heat to medium-high.
Place the seasoned soy curls in the pan in an even layer. Cook, giving them a good stir every 2 to 3 minutes, until they look slightly crisped around the edges, 8 to 10 minutes. Reduce the heat to low.
Add the fettuccine, sauce, and tomatoes and peppers to the pan with the soy curls, tossing to combine all the ingredients well. If the sauce seems too thick, add the reserved pasta water ¼ cup at a time until the sauce reaches the desired consistency. Taste and add salt or more Cajun seasoning if needed.
Serve immediately garnished with parmesan, green onions and parsley.