Mix the soup, Sour Cream, Gouda cheese, 1/2 cup of cheddar cheese, chopped Onion, Worcestershire sauce, and pepper in a mixing bowl.
Spray the slow cooker with cooking spray. Add the Broccoli and Cauliflower florets to the sauce and mix well. Pour into the mixture into the crock.
Sprinkle the crackers/bread crumbs over the top of the mixture. Add several pats of butter on the bread crumbs.
Cook on high for 2 1/2-3 hours. Do not overcook. With 10 minutes remaining lift lid and pour the last 1/2 cup of cheddar cheese over the casserole and recover to let the cheese melt. Cook 4 cups of minute rice on the stove (or do long grain rice in a rice cooker/IP/stove top). Serve the casserole over the rice.