Prepare the oven and cut the vegetables: Place a rack in the middle of the oven and preheat it to 425°F. Then cut the mushrooms and zucchini into large, bite-sized chunks. Cut the eggplant into smaller, bite-sized pieces (about ¾-inch cubes). Peel the carrots, slice them in half lengthwise, and slice them into fairly thin half-moons (about ¼-inch thick).
Season and roast: Place the chopped vegetables onto a large sheet tray. Note: If you don’t have a very large sheet tray, you can use two smaller trays. Just switch their spots halfway through to ensure even roasting. Add the cherry tomatoes as well (halving any particularly large ones), along with the nutritional yeast, onion powder, garlic powder, dried oregano, dried thyme, a big pinch of salt, pepper, red pepper flakes (if using), olive oil, tamari, and ume plum vinegar (or rice vinegar). Toss well to coat. Strain and rinse the cooked lentils, and drizzle with an additional teaspoon of olive oil. Mix well and using your fingers, evenly sprinkle the lentils over the seasoned vegetables. Roast for 30-40 minutes, or until the eggplant morsels are soft, succulent, and completely tender. Once done, give it a toss and taste for seasoning, adding an additional pinch of salt and pepper, if desired.
Cook the pasta: While the vegetables roast, you can cook the pasta according to package instructions. Once al dente, drain, reserving about ¼ cup of pasta water. Return the pasta and pasta water back to the pot and place over just below medium heat. Add a cup of the marinara along with the capers and an additional sprinkle of nutritional yeast. Cook, stirring occasionally, until it thickens and all of the liquid has been absorbed. Remove from heat, crack the lid over top, and set aside.
Make the walnut parmesan: Zest the lemon directly onto the cutting board, and add the walnuts along with a big pinch of flaky salt and an additional teaspoon of nutritional yeast. Finely chop the pile until the walnuts are finely chopped and crumbly.
Assemble and serve: Once both the pasta and the vegetables are done, add the vegetables to the pot and stir well to combine. Transfer to desired serving bowls and use a spoon to add little dollops of the remaining ½ cup of marinara all over the pasta. Garnish with a sprinkling of basil and the walnut parmesan. Enjoy!