Step 1

Add the carrots, potatoes, celery, salt, pepper, thyme and stock to a large saucepan. Bring to the boil and allow to simmer for 15 minutes and then turn off the heat.

Step 2

Take another large saucepan and add in the butter and onions. Heat on medium and cook the onion for about 5-6 minutes until soft. Add in the flour and mix it into the onions and butter using a balloon whisk. It should form into a creamy paste (or roux). Allow the roux to cook for a minute whilst stirring with your whisk, then add in a ladle of the stock from the chicken broth (try to get mostly stock - not the veggies). Stir the broth into the mixture using your whisk. Repeat this until you have ladled out most of the stock from the veggie pan (leaving the veggies behind). Then pour in the milk. Heat through whilst stirring with the whisk. The sauce should thicken slightly as it's heating.

Step 3

Once the sauce is almost at boiling (don't let it boil) add in the veggies and the shredded cooked chicken. Bring back to almost boiling and add in half the lemon juice. Give it a stir and taste. Add the rest of the lemon juice if needed.

Step 4

Add the fresh tortellini and heat through for 2-5 minutes (depending on the size of the tortellini) until hot inside.

Step 5

Season with salt and pepper and sprinkle on some fresh thyme, then serve.