Melt the butter in a heavy bottomed sauce pan. Add the shallots and sweat to soften without colour.

Add the rice and stir constantly until well coated and translucent.

Add the stock, stirring gently. Cook the risotto for 10 minutes. Spread the rice onto a clean tray and allow to cool. Reserve.

Add the following separately stirring: the stock, the parmesan, the mascarpone, the asparagus (cut into diagonal slices) the broad beans, the mint, the lemon.

Keep stirring, and last of all, the Champagne. Adjust the seasoning, if necessary and serve immediately.

(Note: the peas can be used instead of broad beans).