Preheat your oven to 375 degrees Fahrenheit. Grease a 9x13-inch baking dish with non-stick spray and set it aside.

In a large skillet over medium heat, melt 2 tablespoons of butter. Once the butter has melted, add the onions and garlic, and sauté them for about 3 minutes until they become transparent.

Add the chopped carrots and celery to the skillet and continue cooking for another 5 to 7 minutes until they become tender. Sprinkle all-purpose flour over the vegetables and stir until they are well coated and lightly roasted.

Gradually pour in the chicken broth and heavy cream while stirring continuously to avoid any lumps. Keep cooking until the mixture thickens and starts to bubble.

Remove the skillet from heat and add the diced, cooked chicken and peas to the mixture. Stir well to combine all the ingredients.

Transfer the chicken mixture to the prepared baking dish and spread it evenly.

Meanwhile, separate the biscuit dough into 8 pieces and cut each piece into quarters.

Arrange the quartered biscuit dough evenly over the chicken mixture in the baking dish. Melt the remaining 2 tablespoons of butter and brush it over the arranged biscuit dough.

Place the baking dish in the preheated oven and bake for approximately 20 to 25 minutes, or until the biscuit dough turns golden brown and the sides of the dish are bubbly. Allow it to rest for 5 minutes. Optionally, brush the cooked biscuits with any remaining melted butter. Serve immediately by scooping portions.