Preheat your oven to 400°F.
In a large oven-safe skillet, melt the butter over medium heat.
Add the onion, carrots, and celery to the skillet and sauté for 5-7 minutes until softened.
Stir in the minced garlic and cook for 1 minute until fragrant.
Sprinkle the flour over the vegetables and stir constantly for 1-2 minutes to cook off the raw flour taste.
Slowly whisk in the chicken broth and half and half, stirring until the mixture thickens into a creamy sauce.
Stir in the lemon juice, fresh thyme, salt, pepper, cooked chicken, and frozen peas.
Remove from heat and arrange the refrigerated biscuit dough evenly over the top of the chicken mixture.
Transfer the skillet to the oven and bake for 15-20 minutes, or until the biscuits are golden brown and the filling is bubbling.
Let cool for 5 minutes before serving.