This dish is simple and makes an easy light lunch for two. You can use different types of mushrooms if they are available, but the readily available white mushrooms will taste fine.
Heat frypan over medium heat. When the pan is hot, add oil and swirl to coat the pan. Add onions and cook for 1 minute. Add garlic and salt and continue cooking for one more minute. Do not let the onions and garlic brown. If they start to brown, turn down the heat.
Add mushrooms, nutmeg and thyme to pan and cook until the mushrooms have released their liquid and the released liquid has evaporated. Turn up the heat as needed to help evaporate the liquid. This should take only a few minutes.
Add the whipping cream and sour cream. Stir briefly until the cream has thickened up. Sprinkle pepper over and serve on toast.