In a large food processor, blend all the ingredients until crumbled. If your food processor isn't big enough, do the cauliflower and walnuts first, and then the rest.
Preheat oven to 375F. Layer on a lined baking tray the crumbles and bake for 25-35 minutes until golden brown.
Use in tacos, pasta dishes, and so much more! Freeze after cooling for up to 3-4 weeks.