Line a sheet tray with foil and coat with cooking spray.: As you prepare, notice the smooth sheen when you spread the foil, this protective layer keeps the polenta from sticking and makes unmolding easy. The foil should be pressed into the tray corners so the polenta cools in an even layer. A poor lining job will lead to tearing when you remove the set polenta, so take a moment here.
Bring 7 cups of water and salt to a boil.: You will hear the water move from a quiet simmer to a rolling boil, and steam will rise briskly. Adding the kosher salt at this stage dissolves it thoroughly and seasons the entire cooking liquid. If the water only simmers, the polenta may clump when added, so aim for a purposeful boil.
Add polenta in a slow stream while whisking continuously to avoid lumps.: The moment the instant polenta hits the boiling water, whip it in with a steady motion, and you will feel the mixture thicken under the whisk. Keep a quick rhythm, because if the polenta drops in too fast it can form granules that never fully dissolve. A common pitfall is walking away during this pour, which often causes stubborn lumps.
Turn heat to low and continue to stir with a wooden spoon until polenta thickens, 5-8 minutes (you may add more boiling water as needed to keep the polenta a smooth consistency).: As the heat lowers, the pot will emit a gentle bubbling and the polenta will pull away from the sides in waves, signaling it is thickening. Using a wooden spoon gives you tactile feedback; the mixture should feel smooth and slightly resistant on the spoon. If it becomes excessively stiff, whisk in splashes of hot water to regain creaminess. Avoid over stirring at high heat, as prolonged aggressive stirring can break down texture.
Turn the heat off and add parmesan and butter. Stir to combine.: With the heat off, toss in the grated parmesan cheese and the measured butter , then stir until the cheese melts and the butter vanishes into the mass. The aroma will shift to a nutty, savory note as the cheese incorporates. If you add these while the pot is too cool, they may not melt smoothly, so mix briskly to achieve a silky finish.
Pour onto a sheet tray and spread with the back of a spoon to cover the tray evenly. Cool.: Pouring releases a warm, velvety stream that you smooth into an even sheet; the surface should look glossy and free of peaks. The thickness you spread will determine how tall your cutouts are, so aim for uniformity. If you leave air pockets, you may get uneven set points, so press and smooth carefully.
Refrigerate the polenta for 30 minutes or covered up to 2 days.: As the polenta chills, it transitions from soft to firm, and the texture will become sliceable. You will notice condensation on the cover if it sits longer, which is fine. Chilling longer firms the center more, but be aware that extended refrigeration can slightly dry the edges, so cover tightly to maintain moisture.
Remove the sheet tray from the refrigerator and use cookie cutters to stamp out shapes.: When you press cookie cutters into the chilled polenta, you can hear a subtle give as the edges separate cleanly. Press straight down and lift gently to keep shapes intact. If the polenta is too cold and cracks, let it sit at room temperature for a few minutes to soften slightly before cutting.
Heat 1 tbsp of butter in a saute pan over medium heat and cook the polenta shapes for 3-5 minutes on each side or until golden (you can also serve these cold).: As the shapes meet the hot pan, you will hear a satisfying sizzle and smell the rich butter notes. Watch for a golden brown crust forming around the edges, that contrast between crisp exterior and tender interior is the goal. Avoid flipping too early, or they will fall apart; wait until the underside releases easily from the pan.
Eat polenta shapes on their own or serve with a red sauce.: These cutouts offer a warm, creamy center beneath a toasted surface, and the first bite should present a gentle corn sweetness followed by savory cheese. Serving with a bright red sauce amplifies acidity and complements the buttery richness. If the textures seem uniform, consider a quick pan sear to reintroduce contrast.