Using a small spoon, scoop out and discard the black gills from each mushroom.

Heat oil in a large skillet over medium heat.

Add garlic and cook just until it begins to turn light golden brown, about 30 seconds.

Arrange mushrooms in skillet in a single layer then add wine and season with salt and pepper.

Cook, flipping the mushrooms once, until tender and most of the liquid has evaporated, 3 to 4 minutes total.

Set aside off of the heat to cool slightly.

Meanwhile, combine black and green olives, parsley, oregano, vinegar, salt and pepper in a small bowl and press the mixture with the back of a spoon until it's roughly mashed; set aside.

Using your fingers, remove some of the bread from the inside of both halves of the loaf, making sure to keep a 1-inch border around the edge. (This will help to make room for the filling.

Save the bread that you remove for another use, like making breadcrumbs or croutons.)

Layer both halves of bread with olive mixture, then arrange peppers, artichoke hearts, pine nuts and basil on the bottom half.

Top with mushrooms, spreading them out to cover the entire width of the bread.

Assemble the top and bottom halves of the loaf to form a sandwich.

Serve muffuletta right away, or wrap it very tightly with plastic wrap and refrigerate for 1 hour, weighted down with a heavy object like a cast iron skillet filled with a few heavy canned goods.

Cut into wedges before serving.