S'mores pizza

Dough

• 30 g extra virgin olive oil, plus extra to grease
• 220 g lukewarm water
• 1 tsp sugar or malt powder (optional)
• 2 tsp dried instant yeast
• 400 g baker's flour, plus extra to dust
• 1 tsp salt
• 180 g milk chocolate, broken into pieces
• 2 - 3 plain sweet biscuits, crushed
• marshmallows, to decorate