Make one recipe of the garlic herb polenta above and let it set in the fridge.
Preheat your oven to 425 degrees.
If you plan to cook the polenta in the pan you used to let it cool in then place immediately in the oven while the oven and the pan are still cold and let them heat up together. Otherwise cut squares out of the polenta and place on a well oiled baking sheet and spray or brush the tops with oil. Place in the oven and bake till your desired level of crispiness on the bottom(I bake mine till very brown and crispy, but even fairly soft polenta will be delicious) then broil just until the top is golden.
Remove from the oven and turn the oven back to 425 degrees. Top your polenta with your spinach or other greens to which you can also add fresh basil or other fresh herbs which would taste awesome, then add the tomato sauce and then a generous sprinkling of cheese. Return to the oven for about 10-15 minutes until the spinach is wilted, the cheese is melted and everything is heated through. Turn on your broiler again for 2-6 minutes(depending on how close your pan is to the heating element and how hot your broiler gets, as mine has different settings but a lot do not) or until the cheese is golden and bubbly then remove and serve while still hot. Top with fresh basil and Parmesan cheese if desired.