Clean and trim the cauliflower, breaking it into medium sized pieces. Place in a microwave safe bowl with 2 Tbl of cream and 1 Tbl of butter. Microwave, uncovered, on high for 10 minutes. Stir to coat cauliflower with cream/butter mixture. Microwave for another six minutes on high (or until tender.) Remove from the microwave and put into a high speed blender or food processor along with the 8 slices of pepperoni and 1/4 cup mozzarella cheese. Puree until smooth. Season with salt and pepper to taste. You can adjust the cream and butter to your preference for consistency.Spread the cauliflower puree into an 8 x 8 oven proof casserole dish. Cover with 1/2 cup shredded mozzarella cheese, and layer with pepperoni. Bake at 375 degrees (F) for about 20 minutes. Alternatively you could microwave this for 5 minutes. Serve hot.