Place cauliflower in a pot with one inch of salted water, and allow to steam, approximately 5 minute Cauliflower is ready when it gently slides off a fork when stabbed.
Allow cauliflower to cool. While cauliflower is cooling, add chopped onion to a bowl of salted water. Allow to soak 5 minutes, then drain.
Give cauliflower a rough chop to create small pieces, about the size of a dime. It's okay if there are different sized pieces. Place in a large mixing bowl.
Squeeze juice of 6 limes over mixture and mix well.
Add chopped cilantro, drained onions, chopped jalapeño, salt, pepper, and cumin to bowl. Blend well.
Allow mixture to cool in the refrigerator and allow the flavors to mingle if desired. Otherwise, ready to eat immediately!
Ceviche can be served alongside corn tortilla chips or on a tostada.
Optional serving suggestion: Add guacamole to the tostada (as pictured) or add chipotle mayo to the tostada before adding the ceviche for a kick. Optional serving suggestion: Add guacamole to the tostada (as pictured) or add chipotle mayo to the tostada before adding the ceviche for a kick.