I'm partial to
Mother-in-Law's House Napa Cabbage Kimchi (I'll sometimes go half and half with that and the daikon radish kimchi from the same brand) and
Red Boat Fish Sauce, both of which are pretty-widely available (I buy both at Whole Foods). Alternatively, good kimchi and fish sauce are available at most Asian supermarkets. To make vegetarian: seek out vegetarian kimchi and sub soy sauce or tamari for the fish sauce; do note that it will no longer be Whole 30-compliant. The cauliflower can be riced ahead of time and stored in an airtight container or resealable plastic bag in the fridge for a day or two; when you open the container it will be very smelly (don't say I didn't warn you!) thanks to the sulfuric compounds in cauliflower.