Bring a large pot of salted water to a boil and cook your pasta until just al dente, about 8-10 minutes. Drain and set aside.
While the pasta cooks, heat olive oil in a deep skillet over medium heat until shimmering and fragrant, about 1 minute.
Add the minced garlic and chopped onion to the skillet. Sauté, stirring often, until fragrant and translucent, about 2 minutes.
Stir in the chopped tomatoes or canned diced tomatoes. Cook, stirring occasionally, until the mixture thickens slightly and the tomatoes break down, about 10 minutes.
Pour the soaked cashews or coconut milk into the tomato mixture. Use a spoon to mash some of the tomatoes, or blend a small portion of the sauce for a smoother, creamier consistency, and cook for another 3-4 minutes until heated through.
Toss the cooked pasta into the sauce, stirring gently to coat all the noodles evenly. Let them cook together for 2 minutes so flavors meld.
Remove from heat and stir in torn fresh basil, allowing the aroma to infuse the sauce. Season with salt and pepper to taste.
Serve hot, garnished with additional basil leaves or a drizzle of olive oil if desired. Enjoy the creamy, tangy comfort in every bite!