Steam cauliflower and sweet potato in about 1-2″ of water until soft. Alternately, roast on parchment paper in a 400° oven for 20-30 minutes.
Add the softened vegetables to the bowl of your food processor and process a minute to break up the pieces. Or, mash by hand. Add the unsweetened non-dairy milk or broth, garlic powder, salt, and pepper and continue to process until smooth