Step 1

Pre-heat the oven to 450°F. Lightly grease a 2 quart casserole dish and set aside.

Step 2

In a rimmed skillet, cook the onion in 2 tbsps of butter. Once the onion becomes soft, add the quartered mushrooms.

Step 3

Add mushrooms to the skillet and cook for an additional 6-7 minutes.

Step 4

While the mushrooms cook, melt the remaining butter and mix it with the bread crumbs and parmesan cheese. Set aside.

Step 5

Add salt, pepper, and fresh thyme to the mushrooms. Next, add the white wine and allow the mushrooms to simmer and wine to reduce by half.

Step 6

Next, add the flour and the heavy cream. Simmer for 2-3 minutes to allow the sauce to thicken.

Step 7

Pour the mushrooms into the prepared dish. Top evenly with buttered bread crumbs. Garish with a fresh thyme spring.

Step 8

Bake for 10 minutes. The breadcrumbs will be brown and toasted and mushrooms bubbly. Serve.