Preheat oven to 400 degrees F.
Carefully remove stems from mushrooms; chop the stems finely and set aside.
In a large frying pan over medium heat, melt butter. Add chopped mushroom stems, onions, and garlic; saute approximately 5 to 6 minutes or until onions are soft and translucent.
Reduce heat to low; add parsley, cream cheese, blue cheese, lemon juice, and cream sherry or port wine. Stir until cheeses are melted and well blended. Remove from heat.
Season to taste with salt and pepper. You probably won't need any salt, as blue cheese is salty. I do like to add a healthy-grinding of pepper.
Spoon the prepared blue cheese mixture into the mushroom caps, filling generously and mounding the tops. Place stuffed mushroom caps on a baking sheet with sides.
Bake approximately 8 to 10 minutes until mushrooms are cooked and cheese is melted.
Remove from heat and place mushrooms on a large serving plate or platter. Serve immediately.
Makes 24 stuffed mushrooms.
Blue Cheese Stuffed Mushrooms Recipe: https://whatscookingamerica.net/appetizers/bluecheesemushrooms.htm