Bring a pot of water to a boil for the pasta. Add the kosher salt and linguine and cook according to the package directions (I usually cook my linguine for 8 to 9 minutes). Reserving at least ½ cup of the pasta water, drain the pasta. Don’t rinse, but toss with a drizzle of olive oil.
In a large skillet, heat the 3 tablespoons olive oil over medium heat. Add the garlic and corn, plus a dash of sea salt, and cook until the garlic is fragrant and slightly golden, about 3 minutes.
Dissolve the miso in ¼ cup of the hot pasta water, then pour it into the skillet with the garlic and corn. Sprinkle in the nutritional yeast and pepper and stir well. Bring the mixture to a simmer and continue to stir until it is creamy, about 2 minutes. Add more pasta water if you want a thinner sauce.
Add the pasta to the skillet and use tongs to toss and coat. Season to taste with salt and pepper. Serve with red chili flakes (if using), parsley, and walnut parmesan.