Preheat the oven: Preheat your oven to 375°F (190°C).

Prepare the mushrooms: Clean the mushrooms and remove the stems. Place the mushroom caps on a baking sheet, cavity side up.

Make the filling: In a small bowl, mix the shredded Irish cheddar, chopped parsley, and a pinch of salt and pepper.

Stuff the mushrooms: Spoon the cheese mixture into each mushroom cap, filling them generously.

Bake: Bake the mushrooms for 15-20 minutes, or until the cheese is melted and the mushrooms are tender and golden brown on top.

Serve: Serve warm as an appetizer or side dish. Garnish with extra parsley if desired.