Preheat oven to 375 degrees. In a stockpot, heat 1 T. of the olive oil over medium-high heat. Add the onions, carrots, potatoes, and celery. Cook, partially covered, until softened, about 5-8 minutes. (Vegetables will retain a little crunch. If you like your vegetables soft, cook them a few extra minutes). Remove vegetables from pot and set aside.
In the same pot, heat the remaining 2 T. of olive oil. Add the flour and stir. Cook for 1 minute and then add the wine. Stir continuously to make sure there are no lumps and then add the chicken stock, thyme and pepper. Turn down heat and simmer for 3 minutes. Add back the cooked vegetables, peas, and chicken, and stir. Pour mixture into pie plate or square baking dish.
Open biscuit package and peel each biscuit in half and place on top of mixture until entire top is covered with biscuit halves. Place baking dish on baking sheet to catch spills and bake for about 20 minutes until top is golden brown. Remove from oven and allow to cool for a few minutes before serving.