1.Put the dried mushrooms in a small bowl and cover with boiling water. Allow to stand for 5 minutes or until the mushrooms are soft. Drain and finely chop the mushrooms, reserving the liquid.
2.In a medium saucepan, melt the butter, then add the leek and garlic. Cook, stirring, until soft. Add the chopped mushrooms and buckwheat. Stir for a couple of minutes to coat the buckwheat grains in the butter then add the tomatoes and the reserved mushroom liquid.
3.Stir occasionally until the liquid has almost evaporated then add a cup of the vegetable stock. Continue to stir until the liquid has again almost evaporated then add half the remaining stock. Repeat until the stock has all been used and the buckwheat is still a little soupy. Stir in most of the grated parmesan reserving some for sprinkling over to serve and season to taste. Spoon into four warm bowls and top with the baby rocket leaves, a little of the parmesan and a drizzle of extra virgin olive oil.
Not suitable to freeze or microwave.Note