200 g Swiss brown Mercer Mushrooms, finely sliced

20 g Butter

1 Onion, finely sliced

1 Spring onion, thinly sliced

2 Garlic cloves, crushed

2 ½ tbsp Plain flour

½ cup Cream

Salt, to taste

Black pepper, to taste

1 tsp Pesto

6 normal or 12 mini Vol-au-vent cases (homemade or store-bought)

½ Lemon (optional)