In a small pan, sauté minced 4 large mushrooms and ¼ Tbsp. onion in 2 Tbsp. butter for 5-7 minutes. Set aside and let cool.
Set 12 large eggs in a pot of cold water, cover and bring to a boil. Hard boil for 3 minutes, then take off heat and keep covered for 10 minutes.
Take eggs out of hot water and cool down in refrigerator.
Once cooled, cut each egg lengthwise and remove cooked yolks and place in bowl. Set clean egg whites aside on a plate.
In bowl with egg yolk combine cooled sautéed mushrooms and onions, 1 tsp. prepared mustard, 4 Tbsp. mayonnaise, and salt and pepper to taste.
Spoon in yolk mixture evenly in holes of egg whites and lightly sprinkle on top 1 pinch paprika, 1 pinch savory, and 1 pinch parsley. Chill until ready to eat.