A basic approach which has worked with virtually every wild mushroom I've eaten is to simply heat a pan with some butter or olive oil, toss the chopped mushrooms in the oil to coat them over medium-high heat with just a little salt and pepper. Do not overcrowd the pan or they will steam or simmer when they release their moisture, which will toughen them and diminish the flavor; you'll appreciate the scent of them cooking but it's at the expense of flavor and texture.
If a significant volume of moisture is released (and this would happen in the first couple of minutes) you can crowd the mushrooms to one side of the pan and tip it slightly so that the liquid pools in the opposite end. The low end can be centered over the flame until it reduces down and all can be mixed on level ground.
Keep shuffling and turning them in the pan so that they cook evenly. Herbs may also be added, such as thyme, rosemary or tarragon but with a light touch. Once the mushrooms have taken on a golden color, they are fine as is. Take care not to overcook them.
To this elementary method you may first saute onions, leeks or shallots [if you desire, a small amount of garlic may be crushed and chopped, and/or a modest chunk of ginger root might be grated - either or both may be mixed with the onions before they hit the pan so that they cook together] and when they are more or less done, set them aside in a bowl. Proceed with the basic method for mushrooms and during the final moments of their cooking add the still-warm onions, etc from the bowl, stirring them all together until you are satisfied that the mushrooms are done (the onions, etc will only sweeten further during those couple of minutes longer).
If you have the extras, at this time the mushrooms may be removed from the pan and set into a bowl. Some wine may be added to the pan and reduced over a medium-low flame by at least half its volume or more. Add the mushrooms, toss it all in the reduction and kill the flame. Now add a small amount of cream, stirring and shuffling the mix constantly until you see it thicken. Done.
Lay this over rice or pasta with vegetables, fold it into an omelet, spoon it over a baked potato or spread it over toast, it will transform good basic food into something extraordinary.