Clean, clean and halve the mushrooms. Clean, wash and cut spring onions into rings. Wash, clean and halve the tomatoes. Prepare pasta in boiling salted water according to package instructions.
Crisp bacon in a pan, take out and drain on kitchen paper. Pour oil into the pan. Fry the mushrooms for 5-7 minutes. Add spring onions and tomatoes. Deglaze with stock, stir in crème légère and bring to the boil, stir in sauce thickener.
Season with salt, pepper and thyme. Drain the noodles and fold them under the mushroom pan. Crumble the bacon and sprinkle over the mushroom pan.