Rinse the hominy, then place in a large bowl and cover with twice its volume of cold water. Soak overnight. Drain when ready to use.
In a medium saucepan over medium-high heat, add the hominy and twice its volume of water. Bring to a boil, then reduce to a simmer and cook until the hominy kernels have split open and become tender, 1 1/2 to 2 hours. Drain and set aside to cool.
In a medium bowl, add the lime juice and zest, orange juice and zest, tequila, agave, cumin, pepper flakes, salt and black pepper. Whisk together while adding the olive oil in a slow, steady stream.
Add the hominy, black beans, pomegranate seeds and cilantro to the vinaigrette and mix well. Refrigerate for 20 to 30 minutes before serving to allow the hominy and black beans to soak up some of the vinaigrette.