01 -
Set your oven temperature to 175°C (350°F) and let it heat up.
02 -
Slice the baguette into pieces about 2 cm (¾ inch) thick and keep them to one side.
03 -
Heat the butter in a large pan on medium. Toss in the mushrooms and cook them for 2-3 minutes.
04 -
Stir in the onions and keep cooking until both are soft and lightly browned, which takes 5-7 minutes.
05 -
Mix in some oregano, salt, and black pepper to season the onion-mushroom blend.
06 -
Turn the heat down low. Stir in the mozzarella and parmesan until they melt evenly.
07 -
Add the egg into the mix and stir nonstop for about a minute, letting it thicken slightly.
08 -
Turn off the stove and remove the pan once all ingredients are combined.
09 -
Cover a rimmed baking tray with parchment paper.
10 -
Lay the baguette slices on the baking tray. Spoon a good amount of the mushroom mixture onto each slice. Sprinkle a bit more cheese on top.
11 -
For extra taste and a golden touch, carefully drizzle olive oil on top of the toasts, if you’d like.
12 -
Pop the tray into the heated oven and bake for 12-15 minutes until the cheese bubbles and the bread edges are crisp and golden.
13 -
Serve as soon as they’re warm and fresh for best flavor.