Place the chickpeas into the bowl of a food processor fitted with the S-blade. Pulse several times to begin pureeing. Add the olive oil, tahini, lemon juice, and garlic. Pulse again until almost smooth. Next add the avocado. Pulse until completely smooth. Add cumin or cayenne pepper, if desired, and blend. Taste, season with salt, and add additional lemon juice if desired. Puree again until blended.
Transfer to an airtight container and drizzle with olive oil to help prevent browning. Refrigerate until ready to use.
Assemble the salad:
Add the shredded veggies to a medium bowl and drizzle with 2 teaspoons lemon juice. Toss to mix. Set aside.
Add olive oil, 1 tablespoon lemon juice, and quinoa to the jar. Top with veggies, then add avocado hummus, olives, greens, and nuts/seeds in layers.
Top with a tight-fitting lid and refrigerate until ready to eat. The salad can be made the night before, and it will keep for several days in the fridge.
*Can substitute the 1 tablespoon lemon juice with vinegar if desired.