Bring a large pot of salted water to a boil, then cook the ziti until al dente, about 8 minutes. Drain and set aside, reserving a cup of pasta water.
Place soaked cashews into a high-speed blender along with one minced garlic clove, nutritional yeast, lemon juice, and 1/2 cup of water or reserved pasta water. Blend until completely smooth and creamy, stopping to scrape down the sides as needed.
In a skillet over medium heat, warm the olive oil and add chopped onion. Sauté for about 5 minutes until translucent and fragrant, listening for a gentle sizzling sound.
Add the minced garlic to the skillet and cook for another 30 seconds until fragrant, filling the kitchen with a rich aroma.
Pour in the tomato sauce and stir in dried herbs or seasonings if desired. Let it simmer gently for 5 minutes until flavors meld and sauce slightly thickens, filling the air with a garlicky, herbal smell.
In a large mixing bowl, combine the cooked ziti, warm tomato sauce with sautéed onions, and the creamy cashew cheese. Gently fold everything together, adding a splash of reserved pasta water if the mixture seems dry, until well coated.
Transfer the coated pasta mixture into an lightly greased 8x8 inch baking dish, spreading it out evenly. Dollop extra cashew cheese or sprinkle more vegan cheese on top for extra richness.
Bake uncovered in a preheated oven at 180°C (350°F) for 25–30 minutes until bubbling around the edges and the top is golden brown. Listen for a gentle bubbling sound and watch for a slight crisp on the edges.
Remove from the oven and let rest for about 5 minutes; this helps the sauce set and makes serving easier. The aroma of garlic, herbs, and baked cheese will fill your kitchen.
Garnish with freshly chopped basil and serve hot, enjoying the creamy, cheesy texture and golden, bubbly top that invites you to dig in.
