- In a large skillet, brown the mushrooms and onion in the butter and oil. Season with salt and pepper. Sprinkle with the flour and stir to combine. Add the broth and bring to a boil, stirring constantly until it thickens. Add the chicken and tomatoes. Stir to combine and adjust the seasoning.
- Divide among four 1 ½-cup (375 ml) ramekins. Set aside.
- With the rack in the middle position, preheat the oven to 400°F (200°C).
- On a floured work surface, roll out the dough into an 11-inch (28 cm) square. Cut into four squares. Brush the edges with the beaten egg.
- Cover each ramekin with a square of dough, brushed side down, letting the dough drop over the sides. Press the dough on the outer periphery of the ramekins. Brush the surface with the beaten egg. Place the ramekins on a baking sheet. Bake for 30 minutes or until the pastry is golden brown.
Can be frozen before baking.