Carefully unwrap polenta so as not to crumble it and slice the log into 12 even rounds.
Add 2 tbs olive oil to a sauté pan and fry the polenta rounds until crisp. Flip the rounds and continue crisping the other side.
Meanwhile, slice the tomatoes into 12 thick slices and drizzle them with the balsamic vinegar.
Remove the polenta slices from the pan and put them onto a cookie sheet sprayed with non-stick cooking spray. Top each slice with a tomato, salt and pepper to taste, and bake at 350 degrees for 12 minutes.
Once thoroughly heated, top the polenta stacks with a basil leaf and a slice of brie. Return to the oven for 5 minutes or until brie melts. Serve immediately.