- 4 Tbsp butter
- 2 large sweet onions, sliced into thin rings
- 1 pound cremini mushrooms, sliced
- 2 Tbsp olive oil
- 3 cloves garlic, minced
- 2 Tbsp fresh oregano, minced
- 1/4 tsp nutmeg
- 1/2 tsp salt
- 1/2 tsp pepper
- 1 tsp crushed red pepper flakes
- 2 large bunches of Kale, leaves torn and stems removed
- 1/4 cup flour
- 1 cup milk
- 1 cup vegetable broth
- 1/4 cup heavy cream
- 4 cups cooked wild rice
- 2 cups shredded gruyere cheese
- Preheat the oven to 375 F and butter a large casserole dish (I used a 9×13 baking dish) and set aside.
- In a large saucepan over medium heat, melt 2 Tbsp butter, then add the onions. Stir to coat the onions with butter. Continue to cook the onions while you do everything else in the recipe, turning down the heat if needed to keep the onions from burning and drying out. Stir every 5 minutes or so.
- In another large pot, the biggest you have, melt the remaining 2 Tbsp of butter over medium heat. Add the mushrooms, spreading to cover the entire bottom of the pot, and do not stir for about 3 minutes. Stir to get a new layer of mushrooms on the bottom, and cook for another 3 minutes without stirring.
- Add the olive oil if the mushrooms have become dry, along with the garlic, oregano, nutmeg, salt, pepper, and crushed red pepper flakes. Stir to combine, and cook for 30 seconds before adding the torn kale leaves.
- Cook the kale leaves with the mushrooms until the kale is fully wilted. Sprinkle the flour over the mixture, stir to fully incorporate, and then add the milk and vegetable broth.
- Cook, while stirring, until the mixture thickens — about 3 minutes after boiling. Add the cream, stir to combine, and remove from heat.
- Stir the wild rice in with the mushroom mixture, along with 1 cup of the grated cheese. At this point your onions should be caramelized and golden — cook them until they are, and then add to the mushroom mixture.
- Pour the mixture into your prepared pan, and top with the remaining cheese.
- Bake for 20-25 minutes, or until the cheese is fully melted and the casserole is bubbling. Serve hot!