For the burgers, combine the ground beef, bulk sausage pepperoni, green pepper and the remaining half of the onion in a mixing bowl. Add a little salt and pepper and mix with your hands until the sausage and vegetables are well-distributed. Divide the mixture into 4 equal portions and form 4 patties about 1-inch thick.
Preheat a large non-stick skillet over medium-high heat with 2 turns of the pan of EVOO, about 2 tablespoons. Add the pizza burgers to the skillet and cook on each side for 10-15 minutes or until cooked through. Once the burgers are cooked, top some of them with the smoked mozzarella (for those who can eat dairy), and just melt it under the broiler.
While the burgers are cooking, cut the focaccia into 4 equal pieces, like 4 slices of pizza. Slice each triangle of focaccia in half, through the middle lengthwise to create a top and bottom for your burgers. Transfer the cooked burgers to the bottom triangles, top with some of the pizza sauce and then cover with the tops. Serve your pizza burgers with a simple green salad to balance out the meal.