Begin by preheating your oven to 375°F (190°C). This allows for an evenly baked crust.
In a large skillet over medium heat, pour in the olive oil. Once hot, add the chopped onions, diced carrots, and diced celery. Sauté these vegetables for about 5-7 minutes, or until they start to soften and become aromatic.
Sprinkle in the garlic powder, dried thyme, and freshly ground black pepper. Stir the mixture well and let it cook for an additional minute, releasing those fragrant flavors.
Dust the sautéed vegetables with whole wheat flour and mix thoroughly to ensure all pieces are coated. Allow this to cook for another minute to eliminate the raw flour taste.
Gradually pour in the low-sodium chicken broth while stirring continuously. This will help prevent any lumps from forming. Bring the mixture to a gentle simmer and let it thicken for about 5-10 minutes, stirring occasionally.
Once the mixture has thickened to your liking, remove the skillet from the heat. Stir in the shredded chicken, peas, and plain Greek yogurt until everything is combined and creamy.
Lay out your whole grain pie crust or phyllo dough in a pie dish. If you're using phyllo dough, be sure to layer it thickly for a flaky texture.
Pour the chicken and vegetable mixture into the prepared pie crust, spreading it evenly. If you're using a traditional pie crust, cover it with a second layer, seal the edges, and cut a few slits on top to allow steam to escape. For phyllo dough, layer several sheets, brushing each with a little olive oil, and make sure to cut slits on top.
For a beautiful golden crust, beat the egg and brush it generously over the top layers of dough before baking.
Place the pie in the preheated oven and bake for 25-30 minutes, or until the crust is golden brown and flaky.
Allow the pot pie to cool for 5-10 minutes before slicing. This resting time helps the filling set up a bit more.
Notes
Serve with a sprinkle of fresh parsley or thyme for garnish.