Pour 10 cups (2.4L) water in the basin of the Wolf steamer. Heat to HIGH, covered with steamer lid. In solid pan, stir together rice, stock, salt and pepper. Place pan in steamer. Cover with lid and cook for 15 minutes.
Open lid and add zucchini, squash and carrots. Continue cooking for 10 more minutes or until rice is fluffy. While steaming, make the gremolata.
To Make Gremolata:
Combine lemon, parsley and garlic in small bowl. When rice is cooked, drizzle with olive oil. Mix in gremolata.