Bring 3 quarts of water to a boil in a large Dutch oven. Add the cauliflower, and cook for 3 minutes. Add green beans, carrot, and chayote; cover and cook an additional 4 minutes. Drain and rinse under cold water; drain well, and set aside.
Heat oil in pan over medium heat. Add onion, bell pepper, and garlic; cover and cook for 8 minutes or until tender, stirring occasionally. Add cauliflower mixture, salt, cumin, and pepper; cover and cook an additional 5 minutes or until thoroughly heated. Remove from heat, and stir in cilantro.
Note: Zucchini can be substituted for chayote, if desired.