Wash your mushrooms under running water.
Cut them into slices or chunks, however you prefer them.
Put them into a large skillet or flying pan. Don’t worry if the pan is overcrowded. The mushrooms will cook down as the water evaporates.
Add a pinch of salt, and put on a lid on the pan.
Cook over high heat for about 5 minutes.
Remove the lid. The mushrooms should have shriveled up and cooking in a pool of their own juice.
Keep cooking and stirring occasionally, until about 75% of the liquid has evaporated. About another 5 minutes.
Add some butter or olive oil for sautéing. About 1 tablespoon should be enough, but add more if needed.
Lower the heat and continue to stir the mushrooms so they don’t burn.
Cook until all the liquid is gone.
Add the minced garlic and cook until lightly brown and fragment. About 2 minutes.
Remove from the heat.