Pre heat oven to 375 degrees and grease 9x13 casserole dish.
In a skillet over medium heat melt butter and toss in the onion and celery to soften (about 5 minutes)
Toss in the Carrots and season with Salt and Pepper to taste.
Sprinkle with flour and stir. cook for about 1 minute.
Stir in the broth and thyme and bring to boil... stirring occasionally.
Stir in the milk, carrots, peas and lemon juice.
Pour into the casserole dish and bake at 375 for about 20 minutes.
While its in the oven its a good time to make up the biscuits... or if your using the tubed biscuits then maybe its a good time to clean up the mess ;)
Pull out and raise the temp to 425 degrees
Place the Biscuits on top and pop back in the oven for 12-15 minutes.