Truffle flavor here comes from truffle oil, not fresh truffles. For the mushrooms, King Oyster are ideal because their texture mimics truffles, but any mushrooms work. You can swap the 3 Tbsp mushroom protein powder for 2 Tbsp corn starch as a thickener. For a non-vegan version, use regular cream instead of vegan cream and finish with Pecorino Romano or grated Parmesan in place of the protein powder. I use Alpro rice cream for the vegan cream.