Chop the onion and sauté in oil until translucent. Add the roughly diced celery and fry a little. Peel and dice the apple and add to the saucepan with the sliced leek and peas. Add the broth and simmer for 15 minutes. Add the cream to the soup and puree with the hand blender. Season to taste with salt, pepper and a little thyme and simmer for another 5 minutes.
Tip:
If you want to make the soup a little finer, then press it through a sieve to sift out the pea skins.