Cut bread horizontally three times, into four slices of bread approximately ½ inch thick depending on the size of loaf. (Use a long serrated knife for best results.)
Spread a generous amount of Hummus mixture on bottom slice, then cover with next slice of bread. Spread with Tabbouli Salad and cover with next slice. Spread with remaining filling. Top with the crusty slice.
Wrap loaf firmly in plastic wrap. Refrigerate for 1 hour until set. Remove and slice into wedges. Arrange on a serving plate. Cover with plastic wrap to prevent drying out, and let stand a ½ hour to take the chill off before serving.
Note: There are alternative choices to make this recipe gluten-free.