A luxurious side, this one-skillet medley of mushrooms such as shiitake, cremini, trumpet, and oyster, is finished with a touch of cream, a tad of sherry vinegar, and a sprinkle of fresh dill.
Heat a large skillet over medium; swirl in 1 tablespoon oil. Add shallots and cook, stirring occasionally, until crisp-tender and browned in places, about5 minutes. Transfer to a plate.
Return skillet to medium-high. Swirl in 1 tablespoon each oil and butter. Add one-thirdof mushrooms, season with salt and pepper, and spread in a single layer. Cook, undisturbed, until beginning to brown on bottoms, about 3 minutes. Stir and continue cooking until tender and browned, about 2 minutes more. Transfer to plate with shallots.
Cook remaining mushrooms in remaining oil and butter in two more batches. Return cooked mushrooms and shallots with any accumulated juices to skillet. Stir in vinegar, then cream, and simmer until thickened slightly, about 2 minutes. Stir in dill, season with salt and pepper, and serve.