📋 Instructions

1. 1Heat the oven and pan — Heat the oven to 400°F (200°C). Set a 10-inch oven-safe skillet over medium heat and melt the 2 tablespoons of butter until it foams and smells nutty, about 1 minute.
2. 2Soften the onion — Add the diced onion and cook, stirring, until translucent and soft at the edges, 5 to 6 minutes. You should hear a gentle sizzle rather than a sharp crackle.
3. 3Build the sauce — Sprinkle the flour over the onion and stir constantly for 1 minute until it smells toasted and no dry streaks remain. Pour in the milk in a slow stream, whisking, and cook until the sauce thickens enough to coat the back of a spoon, 3 to 4 minutes.
4. 4Fold in the filling — Stir in the Dijon, thyme, salt, and pepper, then fold in the chicken and corn. Taste and adjust the seasoning; the filling should be savory and just a little sweet. Remove from the heat and let it settle for 10 minutes.
5. 5Top with pastry — Lay the puff pastry over the skillet, trimming any excess and pressing it gently against the rim. Brush the surface with the melted butter and cut three small vents in the center.
6. 6Bake until golden — Bake until the pastry is deep golden brown and the filling bubbles at the edges, 25 to 30 minutes. If the top browns too quickly, tent it loosely with foil after 20 minutes.
7. 7Rest before serving — Let the bake rest for 5 minutes so the filling settles. Scatter a few fresh thyme sprigs over the top and serve in warm bowls.