For the quinoa: In a 2-quart saucepan, bring the quinoa, chicken broth, salt and lemon zest to a boil over medium-high heat. Reduce the heat, cover the pot and simmer until the liquid has been absorbed and the quinoa is tender, about 20 minutes. Remove the pan from the heat and allow to rest for 10 minutes.
For the dressing: In a small bowl, whisk together the grapeseed oil, agave, lime juice, vinegar, cumin, salt and pepper until smooth.
In a serving bowl, combine the quinoa, hominy, black beans and cilantro. Add the dressing and toss until coated. Season with salt and pepper. Spoon into the lettuce leaves and serve.