1. In a large bowl toss together the chayote, red cabbage, carrots, jicama, scallions, salt, cumin and coriander. Let the flavors combine while you make the dressing for the slaw.
2. To a food processor add the avocado, crema, orange juice, cilantro, lime juice, agave, jalapeno, hot sauce and minced garlic. Process until completely smooth and season with salt to taste. Refrigerate in an airtight container until ready to serve; the dressing can be made 1 day in advance.
3. When ready to serve toss the dressing with the vegetables. Garnish with the reserved scallions and serve immediately.