Melt the nondairy butter in the same pan. Add in finely diced onion, 1/2 teaspoon red pepper flakes (optional), 1/2 teaspoon oregano, and 1/4 teaspoon thyme to the pan. Add a generous pinch of salt and sauté for 3-5 minutes, or until onion is tender.
Add minced garlic and sauté for another 1-2 minutes.
Stir in the 1/3 cup diced sundried tomatoes and sauté for another minute.
Pour in 1 cup vegetable broth. If any bits are sticking to the bottom of the pan, gently scrape them loose with your wooden spoon.
Stir in the 1 cup cashew cream (or plant-based cream substitute), along with the 1/4 cup shredded vegan parmesan (or 2 tablespoons nutritional yeast). If you are using nutritional yeast, you may need to add in an extra pinch of salt.
Let the sauce simmer, stirring often, until it thickens to a creamy consistency. This usually only takes a minute or two. If it thickens a little more than you prefer, you can simply stir in an extra splash of water or vegetable broth.
Give the sauce and a taste and season to preference with salt. The amount of salt needed will vary depending on the brand of broth and parmesan you used. Chicken-style bouillon tends to run on the salty side, but a regular veggie broth from a carton will likely need extra salt.
Stir in 2 tablespoons fresh basil. Then add the pan-fried tofu back into the pan, gently tossing to coat with sauce. Allow it to simmer for another minute or two to reheat the tofu.
Serve garnished with more fresh basil. Pair with pasta or rice for a satisfying meal.