Cook the farro ahead of time and store in refrigerator until ready to reheat and serve. You can serve this on a large platter plain, or with a side of salsa.
Saute onion mixture in olive oil. Drain the beans and add to the onions. Add the corn, salsa, and cumin. Salt and pepper to taste.
Layer precooked farro (heated) on a large platter. Layer the bean mixtures on top, ending with layered avocado, queso fresco, and chopped cilantro leaves. Serve!