In a large bowl, combine the rinsed black beans, salsa, red pepper, onion (rinse the onion to get a milder onion flavor), garlic, lime juice, and jalapeño and corn (if used). Cut the avocado in half, remove the pit, and cube the flesh. Scoop out with a spoon and add to the bowl. Add the cilantro, cumin and coriander. Mix. If you prefer the chunks of avocado, leave them whole, however I find the salsa tastes better if you slightly mash the avocado (or use guacamole). Let sit in the fridge for at least 30 minutes. Serve with tortilla chips or as a side dish.