Risotto of spring vegetables

INGREDIENTS

• 300g carnaroli rice (risotto rice)
• 150g parmesan , in a wedge
• 20g fresh chives , finely snipped
• 150g shelled broad beans (about 600g in their pods)
• 150g asparagus spears
• 200g shelled small peas (about 800g in their pods)
• fistfuls of ice cubes
• 1 tsp vegetable stock powder, such as Marigold
• 1 large shallot or 2 smaller ones, finely chopped
• 3 large spring onions , trimmed and chopped
• 1 fat garlic clove , lightly crushed
• 2 tbsp olive oil , plus extra to serve
• 50g butter
• 125ml dry white wine
• 2 tbsp mascarpone