4 button mushrooms, thinly sliced
陆 onion, thinly sliced
陆 green pepper, thinly sliced
salt and freshly ground black pepper
1 tsp olive oil, for frying
25g/1oz semi-soft cheese (such as port salut, taleggio or brie)
150驳/5陆辞锄 sirloin steak
1 panini roll or demi-baguette, lightly toasted