Gently wash mushrooms without getting them wetter than necessary.
Heat milk, cream, onion, garlic, bay leaf and mushrooms in saucepan until bubbles form. Set aside for 1 hour. Strain. Discard all solids except mushrooms. Rinse mushrooms. Chop them. You will use ½ cup. Set aside the remainder for another use.

Butter custard or pot de creme cups. Use ¼ cup cheese to coat. Beat eggs and yolks. Add milk, cream, chopped mushrooms, salt and pepper. Sprinkle with remaining ¼ cup of grated cheese. Bake in water bath at 350 degrees for aprox 25 minutes.