4ozyoung porcini or other bolete buttonscleaned, trimmed, and sliced 1/4 in thick
1/4cupyellow sweet oniondiced 1/4 inch
1tablespoongreen garlicdiced 1/4 in (chopped regular garlic can be substituted)
2teaspoonsall purpose flour
1/4cupgrated grana padanoparmesan can be substituted
Preheat the oven to 375.
Heat 1 tablespoon of the oil or lard in a saute pan until nearly smoking. Add the porcini and cook over medium-high heat until browned and caramelized, stirring occasionally, about 5 minutes. Remove the porcini from the pan and season with a pinch of salt and pepper, then add the remaining tablespoon of oil and saute the onion and garlic on medium-low heat, or until translucent and completely cooked through.
Add the porcini and any juice they're given off back to the pan with the onions, add the fresh thyme, then add the tablespoon of butter and heat to melt. Stir in the nutmeg and flour and cook for a couple more minutes, stirring occasionally to remove the raw flavor from the flour. De-glaze the pan with the wine, then stir in the sour cream and cheeses. Double check the seasoning for salt and pepper, and adjust if needed.
At this point the mixture should be thick and creamy, with a consistency a bit thicker than cream sauce. Transfer the mixture to an oven safe casserole and bake until bubbly and browned, about 15 minutes depending on if you have a convection oven or not. Allow the julienne to cool for 5-10 minutes before serving.
I chose young porcini for this, but plenty of mushrooms or a blend would be great too-use your imagination. You can vary the recipe any number of ways by using different cheeses, herbs, or whatever you like.I really like the depth that using two hard grating cheeses brings to this, using soft cheeses like mozzarella that get stringy would be a bit much here, I think, but chevre or another goat cheese would be a great addition.