-
1
Preheat the oven to 375u00b0 F.
-
2
Line a square baking pan with aluminum foil and spray with nonstick cooking spray. Set aside.
-
3
Carefully remove the stems from the mushrooms and discard or save for an alternative use.
-
4
Arrange the mushrooms in the baking pan with the cavities facing up. Set aside.
-
5
Break the stale baguette into large chunks and place in the bowl of a food processor. Pulse into coarse crumbs.
-
6
Place the breadcrumbs into a mixing bowl. Add the parsley, thyme, garlic powder, salt, and pepper.
-
7
In a separate bowl, whisk together the egg, mayonnaise, and Dijon mustard.
-
8
Pour the egg mixture over the breadcrumbs.
-
9
Using a large fork, mix until the ingredients are thoroughly combined and the stuffing holds together when pinched.
-
10
With a small spoon and clean hands, stuff a generous Tablespoon of filling into each mushroom. Pack the filling tightly into each cavity, using enough so that the mushrooms are domed with stuffing.
-
11
Transfer the baking pan to the preheated oven.
-
12
Bake for 23-26 minutes, until the mushrooms have released some of their juices and the stuffing is nicely browned.
-
13
Remove the pan from the oven. Allow the mushrooms to cool for 5 minutes before plating and serving.
