Preheat a stovetop grill or griddle. Cut the bread in half lengthwise. Hollow out the insides. Set aside
Make compound butter by combining butter, olives and oregano.
Spread and even layer of compound butter on each cut surface of bread. Reassemble the pieces.
Brush outside of bread with the olive oil and season with salt and pepper.
Place the bread on the griddle and top with pans or other type of weight to gently press the bread while it is toasting. Griddle or grill about 4 minutes on each side, or until golden brown.