Start by stirring melted butter and minced garlic in a large bowl. Toss in the cubed bread until it’s evenly coated in the garlic butter. Set the aromatic pieces aside while you move on to prepping the filling.

Heat olive oil over high heat in your oven-safe skillet. Add the mushrooms in a single layer, cooking until they’re golden brown and packed with savory umami flavor. Set the cooked mushrooms aside for later.

Reduce the heat and melt butter in the same skillet. Add the chopped onion and minced garlic, stirring until they soften and release their aroma. Then, toss in the diced carrot and cook for a couple of minutes to get it slightly tender.

Stir flour into the buttery vegetable mixture to form a roux. Slowly pour in the milk while whisking constantly to create a smooth, thick sauce. Add the chicken stock, salt, and black pepper, stirring it all together. The sauce should start to thicken slightly as it simmers.

Fold the cooked turkey, frozen peas, and sautéed mushrooms into the sauce. Stir gently until the filling is well combined and evenly coated in the creamy sauce. Spread this mixture evenly across the skillet.

Layer the garlic butter-coated bread pieces across the filling, covering the entire surface. Sprinkle Parmesan cheese on top (if you’re using it), followed by a generous layer of mozzarella.

Place your skillet in a preheated oven (180°C/350°F) and bake uncovered for about 12-15 minutes. This will create beautifully golden brown, crispy bread chunks. Then, loosely cover the skillet with foil and bake for an additional 10 minutes to finish cooking the filling.

Remove your pot pie from the oven and sprinkle with fresh Parmesan or herbs as a garnish. Serve it hot, and watch as everyone digs in for seconds (or thirds!).