Crispy Parmesan Polenta Squares with Garlic-Balsamic Mushrooms

Make it

Instructions

1. 01

   Prepare the pan and mise en place

   Set an oven rack in the center position. Line an 8-inch square baking dish with parchment paper, leaving a 2-inch overhang on two sides, then grease the parchment and exposed sides with 1 tbsp olive oil. Measure the remaining ingredients and keep a whisk, heatproof spatula, large saucepan, large skillet, and rimmed baking sheet nearby. | Why: Lining and greasing now ensures the chilled polenta releases cleanly for crisp baking later.

2. 02

   Cook the Parmesan polenta

   In the large saucepan, bring 4 cups vegetable broth and 1 tsp kosher salt to a full boil over high heat. While whisking constantly, slowly stream in 1 cup polenta. Reduce to low and cook for 20 minutes, whisking every 2 to 3 minutes and scraping the corners, until thick, glossy, and tender with no gritty bite. Remove from the heat; stir in 2 tbsp unsalted butter and 1/2 cup Parmesan cheese until melted and creamy. Taste and adjust the seasoning only if needed. | Why: Slow whisking hydrates the grains evenly, while butter and cheese make the set polenta rich enough to crisp beautifully.

3. 03

   Set and chill the polenta

   Immediately scrape the hot polenta into the lined and greased baking dish. Smooth it into an even layer with the spatula, then let it cool uncovered on a rack for 20 minutes, until no longer steaming. Cover and refrigerate for 30 minutes, until firm enough to cut into neat squares. | Why: Cooling before covering prevents condensation, and chilling firms the polenta so it can develop crisp edges instead of slumping.

4. 04

   Bake the polenta squares

   While the polenta chills, heat the oven to 425°F and line the rimmed baking sheet with parchment paper. Lift out the firm slab using the paper overhang; cut it into 8 equal rectangles. Arrange the rectangles on the lined sheet with space between them and bake for 20 minutes, flipping carefully halfway through, until both sides are golden brown and crisp at the edges. | Why: High heat dries and browns the surface, creating a sturdy, crunchy base for the saucy mushrooms.

5. 05

   Brown the mushrooms

   While the polenta bakes, wipe the skillet clean and heat it over medium-high heat. Add 1 tbsp olive oil and 12 oz cremini mushrooms in a single layer. Leave them undisturbed for 3 minutes, then cook for 5 to 7 minutes more, stirring occasionally, until their moisture has evaporated and they are deeply browned. Reduce the heat to medium; add 3 garlic cloves, 1/2 tsp dried thyme, 1/4 tsp black pepper, and 1/4 tsp kosher salt. Stir for 30 seconds, just until fragrant. Add 2 tbsp balsamic vinegar and cook for 1 to 2 minutes, scraping up the browned bits, until the mushrooms are glossy and the skillet is nearly dry. | Why: Browning concentrates the mushrooms' savory flavor; garlic and balsamic added late stay aromatic and bright rather than scorching.

6. 06

   Finish and serve

   Turn off the heat and fold 2 tbsp flat-leaf parsley through the glossy mushrooms. Place two hot polenta squares on each plate, spoon the mushroom mixture over them, and serve immediately while the polenta edges are crisp. | Why: Adding parsley off heat preserves its fresh color and clean flavor, balancing the rich polenta and savory mushrooms.