Heat a large saute pan or saucepan over a medium high heat. Add the oil, onion and celery and sweat for about 15 to 20 minutes, stirring regularly. Do not colour, just soften. Add a little water if it looks like they are starting to colour.
1 tbsp Light olive oil, 2 sticks Celery (about 130g), 1 Medium onion (about 100g)
Put the porcini mushrooms in a bowl and pour 100ml of boiling water over the top. Allow to stand for 15 minutes.
15 g Dried porcini mushrooms, 100 ml Boiling water
Add the sliced white mushrooms to the onions and celery, season with salt and pepper and fry for around 5 - 10 minutes, until just starting to colour, stirring regularly.
250 g White mushrooms, Salt & pepper
Add the garlic and fry for around 2 minutes, stirring well.
2-3 cloves Garlic
Add the Arborio rice to the saucepan, stir well and cook for 1 minute. Then add the dry vermouth and cook for a further minute.
250 g Arborio rice, 100 ml Dry vermouth
Transfer the rehydrated porcini mushrooms to a chopping board (whilst retaining the soaking liquid) and slice finely. Add to the saucepan.
Add all of the vegetable stock to the pan and stir well. Cook for 20 - 25 minutes over a medium high heat, stirring very regularly.
1.2 litres Boiling water, 1 each Vegetable stock cube