Brush and wash the Verona celeriac well and cook it in boiling water. Cut into pieces and emulsify in a blender together with the olive oil. Add salt and pepper to taste. In a saucepan brown the rice with 20 g extra virgin olive oil. Add all the boiling stock in one go, stir delicately, cover with a lid and lower heat to minimum. Cook for 10 minutes. At this point add the pureed celeriac and finish cooking. Cream with the knob of butter and the Parmesan cheese. Serve and garnish the dish with the celeriac cut into Julienne and lightly tossed in extra virgin olive oil.