Wipe mushrooms clean with a damp cloth. Carefully remove stems and set caps aside on the prepared sheet, cavity side up. Finely chop the stems and reserve for the filling.

Lightly brush the mushroom caps with 1 tbs olive oil and season inside and out with 1 tsp salt and 1/2 tsp black pepper. Set aside.

Make prawn filling

Heat a medium skillet over medium heat and melt 2 tbs unsalted butter. Add the finely chopped shallot and sauté 2–3 minutes until translucent.

Add the minced garlic and the reserved chopped mushroom stems. Sauté 1–2 minutes until fragrant and the stems have softened.

Add the finely chopped prawns and cook, stirring, 2–3 minutes until they turn pink and are just cooked through. If using white wine, pour 2 tbs now and simmer 1 minute to reduce.

Remove from heat. Stir in 2 tbs chopped parsley, 1 tsp lemon zest, 1 tsp lemon juice, 1/2 tsp salt, 1/4 tsp black pepper and 1/4 tsp red pepper flakes if using. Taste and adjust seasoning. Let the mixture cool 3–5 minutes.

Assemble with cheese

Fold 3 tbs softened cream cheese into the slightly cooled prawn mixture until evenly combined. The mixture should be moist but firm enough to mound — if too loose, chill 5 minutes.

Spoon an equal amount of the prawn-cheese mixture into each mushroom cap, mounding slightly above the rim.

Sprinkle the tops with 50 g grated mozzarella and 25 g grated Parmesan. If you want a crisper top, lightly dust each with about 1/2 tbs of breadcrumbs (using 2 tbs total).

Bake and finish

Place the filled mushrooms on the prepared baking sheet. Brush the exposed mushroom edges with 1 tbs melted butter.

Bake in the preheated oven 12–15 minutes until cheese is melted and bubbly and tops are golden. If you like extra browning, place under a hot broiler for 1–2 minutes, watching carefully to avoid burning.

Remove from oven and let rest 2 minutes. Garnish with 1 tbs chopped fresh parsley and serve immediately with lemon wedges for squeezing over the mushrooms.