1 Casserole dish Approximately 2 quarts--I used a white 8" round
Ingredients
For the Veggies & Aromatic Base
4tbspunsalted butter
1small yellow onionfinely diced
2celery ribssliced
2medium carrotssliced into thin rounds
3 to 4clovesfresh garlicfinely minced
1/4cupall-purpose flour
For the Filling
2 to 3cupsrotisserie chickenshredded or cubed
1 1/2cupschicken broth
1/2cupheavy creamor whole milk
1cupfrozen peas and corn blend
1tspdried thyme
Salt and black pepper to taste
1Small lemonjuice and zest
For the Garlic-Herb Pastry Topping
1sheet store-bought puff pastrythawed
1large eggbeaten (for egg wash)
1/2tspgarlic powder
1/2 to 1tspHerbs de Provencecrushed between fingers (see note)
1/2tspflake saltlike Maldon
Instructions
Prep the Pastry & Oven
Preheat your oven to 400°F (200°C).
Unroll the thawed puff pastry onto a lightly floured surface.
Optional Fit: Place your CorningWare dish upside down on the pastry and cut a circle 1 inch wider than the rim (or leave it square for rustic overhanging corners).
Sauté the Aromatics on the Stovetop
Melt the butter in a large skillet or saucepan over medium heat.
Whisk in the thyme then add the onion, celery, and carrots.
Sauté for 6 to 8 minutes until the vegetables soften.
Stir in the minced fresh garlic for the last 60 seconds until fragrant. Do not let it burn.
Build the Velvet Gravy
Sprinkle the flour evenly over the sautéed vegetables.
Stir constantly for 1 to 2 minutes to cook out the raw flour taste.
Slowly pour in the chicken broth and heavy cream while whisking continuously to eliminate lumps.
Simmer for 3 to 4 minutes until the sauce thickens into a rich gravy.
Finish and Transfer the Filling
Fold in the chicken, frozen peas, corn, and dried thyme.
Fold in the lemon juice and zest
Taste the gravy and season with salt and black pepper as needed.
Pour the hot, bubbling filling directly into your ungreased, room-temperature CorningWare dish. [1]
Dress the Gourmet Crust
Drape the puff pastry sheet over the hot filling in the CorningWare dish.
Cut 3 or 4 small slits in the center of the pastry to let steam escape.
Brush the top generously with the beaten egg wash.
Sprinkle the garlic powder and crushed Herbs de Provence evenly over the wet egg wash.
Crush the flake salt gently between your fingers and rain it over the top.
Bake and Serve
Bake for 20 to 25 minutes.
Remove when the pastry is fully puffed, crisp, and deep golden-brown, with filling bubbling at the edges.
Rest the hot dish on a wooden cutting board or thick trivet for 5 minutes before scooping to prevent thermal shock to the ceramic.
Notes
If you don't have herbs de Provence in your kitchen, it's just a traditional mix of Mediteranean spices like like thyme, rosmarry, savory, and oregeno.