Grease a half sheet pan (12-by-17-inch) and set aside. Prepare the filling by mixing together the walnuts, sugar and cinnamon. Set aside.
Open the package of phyllo dough and lay it out on the table covered with a cloth when not using it. Take one sheet of dough at a time and fold it in half width-wise (like a book). Brush/blot lightly with butter, sprinkle about 1 1/2 tablespoons of filling over most of the dough, leaving about 2 inches free at the top edge. Fold 1 inch over at the bottom and place the dowel here. Roll up from this end, finishing at the filling-free end.
Set the seam side down. Push the two ends together toward the center using both hands, giving the dough a crinkled look. Remove the dowel and place the bourma on the greased sheet. Repeat with the rest of the dough and then brush the tops of all of them liberally with melted clarified butter. Cut off the ends of each bourma and then cut the center part in half, creating two bourma baklava per roll with the trimmings on either side.
Bake at 350 degrees F for about 35 minutes until nice and golden brown. Meanwhile, prepare the syrup by dissolving the sugar in the water over high heat. Bring to a boil then add the lemon juice and cloves, lower the heat and simmer for about 10 minutes. Set aside.
When the bourma baklava is completely cool, and the syrup is warm, but not too hot (about 160 to 165 degrees), ladle the syrup over the pan and let it soak in until mostly absorbed. There will still be some syrup left in the pan, but most of it should soak into the dough. Use a sharp knife and go over all the previous cuts, making sure the bourma baklava is cut all the way through before serving. Store at room temperature.