I made these little guys for a little impromptu fall gathering and they went like, well, mini pizzas. Not only were they delicious, but they were super easy to make. Just buy a couple of tubes of prepared polenta (I prefer the organic brand at Whole Foods), a couple of jars of spaghetti sauce (I used garlic and herb), and a large bag of shredded mozzarella cheese (normally I would use fresh mozzarella but I didn't have any on hand). I kept the ingredients simple, but you can definitely add any other toppings, just keep in mind that these pizzas are very mini so it's better not to overdo it.
Preheat oven to 350 degrees and slice the polenta into about 1/3” rounds and then layer with your ingredients. Sprinkle with fresh ground pepper. Assemble on a cookie sheet (I used a silpat, but you can just spray a cookie sheet with Pam or even oil) and cook for approximately 30 minutes.