4 to 6 tablespoons extra-virgin olive oil
2 pounds mixed wild and cultivated mushrooms, cleaned, trimmed, and thickly sliced
Kosher salt and freshly ground black pepper
1 or 2 shallots, peeled and finely chopped
2 garlic cloves, peeled and finely chopped
2 tablespoons unsalted butter
2 tablespoons fresh thyme leaves
2 tablespoons chopped fresh tarragon (optional)

Heat about 1 tablespoon of the oil in a large, heavy skillet over medium-high heat until it shimmers. Add just enough mushrooms to loosely cover the bottom of the skillet (you should be able to see the pan between the mushrooms). Season the mushrooms with salt and pepper. Cook for about 2 minutes, then gently turn the mushrooms over as they brown and soften.

Add a little chopped shallot and garlic, some butter, and some thyme and tarragon. Continue cooking the mushrooms until they are tender, about 2 minutes more, then transfer then to a paper towel. Wipe out the skillet and repeat the process, cooking the mushrooms in small batches.