Rinse the peas under cold running water. Put in a saucepan and cover generously with water. Bring to a boil and boil for 3 minutes, skimming off the foam from the surface. Drain the peas.

Heat the oil in a large saucepan over medium heat. Add the onion and cook for 3-4 minutes, stirring occasionally, until just softened.

Add the carrot and celery and continue cooking for 2 minutes. Add the peas, pour over the stock, and stir to combine.

Bring just to a boil and add the thyme, marjoram and bay leaf. Reduce the heat, cover and cook gently for 1-1 1/2 hours, until the ingredients are very soft. Remove the bay leaf.

Taste and adjust the seasoning, adding salt and pepper to taste.

NOTES: I've adjusted this from a recipe in "Irish Pub Cooking". The original recipe called for 8 ounces of lean smoked ham, half the seasonings that I've used, one-fourth of the carrots & celery, and just 4 cups of stock with 4 cups of water. Since I was leaving out the ham, I increased the seasonings, vegetable and stock to add flavor and make it more of a full soup.