A duxelles of mushrooms is one of the oldest, time-tested ways to preserve your harvest. This is a small batch, scale as needed for large harvests. I mostly make this in quantities of 2+lbs, but making a small batch will help you get the feel for the process.
1lbfresh wild mushrooms cleanedcaps and stems roughly chopped.
1Tbspshallot diced ¼ inch or chopped roughly
¼Teaspoonfresh ground black pepper
2tbspoilplus a little extra for roasting afterword
¼cupdry sherrydry white wine can be substituted
1/2teaspoonfresh chopped thyme
Finely chop the mushrooms by hand, or pulse the mushrooms in a food processor until they're finely chopped, but be careful not to over-process them. Traditionally you would chop them by hand, and it will give the best texture.
Heat a large saute pan with the oil. Heat the pan until hot and nearly smoking, then add the mushrooms and shallots, and stir to coat with the oil. Cook for a minute or two, stirring occasionally.
Add the salt, pepper and the herbs. Continue to cook, lowering the heat to medium to prevent scorching. Cook the mixture for ten minutes, until the mushrooms have given up their water and the pan starts to look dry.
Deglaze the pan with the sherry or wine, then cook off the liquid again until the pan is dry, stirring the pan to coat the mushrooms with the juices. From here, if you like the flavor, you can cool the duxelles and refrigerate them for a few days, or freeze right away for later. If the duxelles taste mild to you, as may happen if you're making a large batch, proceed to drying them out in the oven.
Drying/roasting the duxelles to finish
After cooking, spread the duxelles onto a cookie sheet, spray or brush lightly with oil, then cut a cross-hatch pattern in them with a spatula.
Bake the duxelles for 15-20 minutes at 400F, or until you like the flavor, taking them out of the oven half-way through roasting to turn them over with a spatula to reveal the light-colored mushrooms underneath and encourage even caramelization. Cool the duxelles, then refrigerate or freeze.
After cooking, a great way to preserve them is to pack into ice cube trays and freeze, then pop out the cubes seal in a re-sealable vacuum freezer bag. This is a relatively small batch, so feel free to scale it up.