Garlic Butter Mushrooms with Creamy Polenta and Fontina Step-by-step instructions

Before you start

Before cooking, clean the mushrooms and score the king oyster caps. Grate the fontina and Parmesan, and pick the thyme leaves. Measure the polenta and water. Have the butter, garlic, and seasonings within reach.

Set a large cast iron skillet and a medium saucepan on the stove. The whole dish comes together quickly once you start cooking, so having everything prepped is key.

Instructions

Prep and Polenta

1. 1Prepare the mushrooms and cheese
   Clean the king oyster and cremini mushrooms with a damp paper towel. Trim the tough ends from the king oyster mushrooms, then score the caps in a diamond pattern, making shallow cuts about 1/4 inch deep. Leave the cremini mushrooms whole if small, or halve any large ones. Grate the fontina cheese on the large holes of a box grater into a bowl. Set aside.
   Look for The mushrooms are clean and scored; the fontina is grated into a fluffy pile.
   Tip Scoring the mushrooms helps them absorb the garlic butter and creates more surface area for browning.
2. 2Start the polenta
   In a medium saucepan, bring the water to a boil over high heat. Slowly whisk in the polenta in a steady stream, reduce the heat to low, and cook, stirring frequently, until the polenta is thick and creamy, about 5 to 7 minutes for quick-cooking polenta. Season with salt and pepper. Keep warm over very low heat, adding a splash of water if it becomes too thick.
   Look for The polenta is smooth and pulls away from the sides of the pan.
   Tip Whisk constantly to prevent lumps. If the polenta thickens too much, stir in a little hot water.

The mushrooms are prepped and the cheese is grated. The polenta is simmering and will be ready to hold. The kitchen smells of cornmeal and butter. The mushrooms are ready to hit the hot skillet.

Sear and Assemble

3. 3Sear the mushrooms in garlic thyme butter
   In a large cast iron skillet over medium-high heat, melt the butter until it foams. Add the garlic and thyme leaves, and cook for 30 seconds until fragrant. Add the mushrooms in a single layer, cut-side down if scored. Sear without moving for 3 to 4 minutes, until deep golden brown. Flip and sear the other side for another 3 to 4 minutes. Season with salt and pepper.
   Look for The mushrooms are deeply browned with crisp edges, and the butter smells nutty and garlicky.
   Tip Do not overcrowd the pan; work in batches if needed to get a proper sear.
4. 4Spoon mushrooms over polenta
   Spoon the creamy polenta onto serving plates or a large platter. Top with the seared mushrooms, including all the garlic and thyme from the skillet. Pour any remaining garlic butter over the mushrooms.
   Look for The polenta is spread in an even layer, and the mushrooms are piled on top.
   Safe temperature 145°F (63°C) internal temperature (shellfish)
   Tip Use a large spoon to create a slight well in the polenta to hold the mushrooms and butter.

The mushrooms are deeply browned and glistening with garlic butter. The polenta is creamy and spread on plates. The mushrooms are spooned over, and the fontina is scattered on top, starting to melt from the residual heat.

Melt and Finish

5. 5Melt the fontina over the top
   Scatter the grated fontina cheese evenly over the hot mushrooms and polenta. The residual heat will melt the cheese, but for a more molten result, place the serving dish under a hot broiler for 1 to 2 minutes, watching closely, until the cheese is bubbly and golden in spots.
   Look for The fontina is melted and creamy, with some golden spots if broiled.
   Tip If broiling, use an oven-safe dish and keep a close eye to avoid burning.
6. 6Finish with Parmesan and thyme
   Shower the dish with the grated Parmesan and fresh thyme leaves. For a dramatic finish, pull a portion of the melted cheese into a long stretchy ribbon and drape it over the top. Serve immediately.
   Look for The Parmesan and thyme add a final savory, herbal note.
   Tip The cheese pull is easiest when the fontina is still hot and molten.

The fontina is fully melted and stretchy, the Parmesan and thyme are sprinkled on, and the cheese pull is dramatic.

The dish is ready to serve immediately. Take a moment to check the color, texture and aroma before you move on to the next step.

Common mistakes

One common mistake is overcrowding the skillet, which steams the mushrooms instead of searing them. Work in batches if necessary. Another is using cold butter, which can burn before the mushrooms are cooked; let it melt and foam gently.

Skipping the scoring on the king oyster mushrooms means they won't absorb as much butter or look as impressive. Finally, don't let the polenta sit too long without stirring, or it will become lumpy.

How to tell it’s done

The mushrooms are done when they are deeply browned on both sides and tender throughout; the edges should be crisp but not burnt. The polenta should be thick enough to hold its shape on a spoon but still creamy and pourable.

The fontina is melted and bubbly, with a golden top if broiled. The dish is meant to be served hot, straight from the pan, with the cheese pulling in long ribbons.

• Shellfish: 145°F (63°C) in the thickest part