Cook rice in 2 qts. of water until just bloomed (about 40 min.).
Melt butter and saute carrots & leeks over medium-high heat for about 10 minutes. Add mushrooms and cook until soft; add flour and stir well.
Deglaze pan with sherry and reduce a little. Add vegetable stock and cook until blended - about 30 minutes. Add wild rice & heavy cream and bring back to heat. Add herbs and season with salt and pepper.