Divide the polenta among shallow bowls and top with the shrimp and sauce. Serve hot!
Bring 3 cups of vegetable broth to a boil in a heavy medium saucepan. Add 1 teaspoons of salt. Gradually whisk in the cornmeal. Reduce the heat to low and cook until the mixture thickens and the cornmeal is tender, stirring often, about 15 minutes. Turn off the heat. Add the butter and grated Parmesan, stir until melted. Your polenta is ready. Season the shrimp with salt and pepper. Heat the olive oil in a large skillet over medium-high heat. Add the shrimp, garlic and cayenne, if using, and cook, tossing, until the shrimp are pink, 4 to 5 minutes. Remove from the heat and add the lemon juice, zest and parsley, add splash of water. Stir to coat the shrimps with the sauce and season to taste with salt and pepper.