Make the Polenta:

1. Prepare Pan: Line a 9×13-inch baking dish or rimmed sheet pan with parchment paper or plastic wrap, leaving overhang on sides for easy removal. Lightly oil or spray.
2. Boil Liquid: In a large saucepan, bring water or broth and salt to a rolling boil over high heat.
3. Add Polenta: Reduce heat to medium-low. Slowly pour polenta into boiling liquid in a steady stream while whisking constantly to prevent lumps. This step is crucial—add slowly while whisking vigorously.
4. Cook Polenta: Continue cooking, stirring frequently with a whisk or wooden spoon, until polenta is thick and creamy and pulls away from sides of pan, about 20-25 minutes. It should be thick enough to hold its shape on a spoon. Reduce heat to low if it’s sputtering.
5. Add Enrichments: Remove from heat. Stir in butter (or olive oil) and Parmesan cheese if using. Mix until fully incorporated.
6. Spread and Cool: Pour hot polenta into prepared pan. Use a spatula to spread evenly to about ½-inch thickness. Smooth the top. Let cool at room temperature for 15 minutes, then refrigerate for at least 2 hours (or overnight) until completely firm.

Bake the Fries:

7. Preheat Oven: Preheat oven to 425°F (220°C). Line a large baking sheet with parchment paper or silicone mat.
8. Cut into Fries: Once polenta is completely firm, lift from pan using parchment overhang. Place on cutting board. Using a sharp knife, cut into fry shapes—about ½-inch wide by 3-4 inches long. You should get 30-40 fries.
9. Season Fries: Place fries on prepared baking sheet in a single layer, not touching. Brush or drizzle with olive oil, making sure all sides are coated. Sprinkle with salt, pepper, and any optional seasonings.
10. Bake: Bake for 25-30 minutes, flipping halfway through (at about 12-15 minutes), until golden brown and crispy on edges. For extra crispiness, broil for final 2-3 minutes, watching carefully.
11. Serve: Serve immediately while hot and crispy with your favorite dipping sauces.