Whisk together soy sauce, vegetable stock, brown sugar, ginger, garlic, and sesame seeds, and set aside. If you prefer a thicker sauce, add 1 tablespoon of cornstarch before cooking.
Cook cauliflower rice and vegetable stock, covered and over medium heat for 15 minutes.
Heat sesame oil in a large skillet, and cook carrots over medium-high heat for 7-8 minutes; stirring 1-2 times, until they begin to soften.
Add peppers, broccoli, and zucchini; stir. Cook covered for an additional 7-8 minutes.
Pour sauce over vegetables and cook a final 7-8 minutes, stirring frequently.