Preheat oven to 425 degrees F.
In a small saucepan, heat olive oil over medium heat. Add garlic and cook 3-4 minutes, until softened and fragrant. Remove from heat.
Cut each tube of polenta in to 11 slices, 1/2" thick each. Place on a prepared baking sheet, brush with 1 tablespoon of the garlic oil, and season lightly with salt and pepper. Bake 15 minutes, turning once. Remove from heat and turn oven down to 350 degrees F.
In an extra-large skillet, heat the remaining garlic oil over medium high heat. Add pepper, zucchini, and mushrooms. Cook 5-6 minutes, stirring frequently, until vegetables are crisp-tender. Season with salt and pepper, to taste.
In a 9" spring form pan, layer the first 11 slices of polenta. (There will be gaps; that's okay, just make sure the slices are touching.)
Layer as follows: 1/2 cup mozzarella, 1/2 cooked vegetables, 1/2 cup mozzarella, the remaining 11 slices of polenta, 1/ 2 cup mozzarella, the remaining cooked vegetables, all the tomatoes, the remainder of the mozzarella.
Bake 35 minutes. Remove from oven and allow to stand 15 minutes. Run a knife around the pan to loosen the edges. Carefully remove the sides of the pan.
Sprinkle torte with basil and serve warm.