Preheat oven to 375 ℉ / 190 ℃.
Heat oil in a skillet over medium-high heat.
Sauté onions until translucent, then add garlic.
Cook for 3-5 minutes, or until slightly browned.
Add spinach, and cook for 2 to 3 minutes, or until wilted. Set aside.
Blend tempeh, cream cheese, basil, and nutritional yeast, until the mixture is thick and smooth. Add splashes of water to help lubricate if necessary, salt and pepper to taste.
Combine pasta sauce and salsa.
Spread tomato mixture on the bottom of a 13- x 9-inch baking dish
Cover with one-third of the noodles (4 or 5 noodles), spread a thin layer of cream cheese mixture, then veggies, and ladle on another one-quarter of the sauce.
Repeat the layer of noodles, filling, and veggies. Finish with a final layer of noodles and the remaining sauce.
Cover lasagna with foil, and bake for 30 minutes.
Uncover, and bake for 15 minutes more, or until noodles are tender.
Sprinkle vegan parmesan to cover the pan, and cook for 5 more minutes. Remove from oven, and let stand 10 minutes before serving.