I'm trying to make pizza that's comparable to ones you get at restaurants. It's pretty good, but it's lacking those classic brown spots on the cheese. I'm using pre-shredded mozzarella cheese, so I thought that the rice flower anti-caking agent added to it makes it harder to brown? I am not using a pizza stone either, and am cooking my pizza at 425F for 15 min I get melted cheese, but it's completely white, with splotches of red sauce. It looks like I poured Elmer's glue all over my pizza. What can I do to get my pizza cheese to brown right? 
It isn't browning because the top of your pizza is not getting hot enough to brown the cheese. One solution for baking pizza in a home oven is to use the broiler near the end of your bake time. You can also place your rack as high as possible, cooking as close to the top as you can. Just keep an eye on the broiler situation if you do this, and also use the broiler step I suggested. 