In a frying pan sauté the spinach for about a minute then add to it the pressed garlic. Stir till the spinach is wilted, then remove from heat.
For the mushrooms either peel their skin off or clean them.
Crumble the white soft cheese using a fork in a bowl and combine with it the sautéed spinach.
Fill each mushroom with about 1 tsp of the wilted spinach and white soft cheese mixture.
Place on a baking tray and bake in a preheated oven at 200°C for 20 minutes.
Serve warm or cold.