Cold Flatbread Pizzas

Ingredients

• 4 tbsp balsamic vinegar
• 8-10 tbsp olive oil
• 1 pinch granulated sugar
• 1/2 lb buffalo mozzarella, diced
• 1 - 13.5 oz can artichoke hearts, drained and sliced
• 2 - 7 oz cans tuna, drained
• 7 None tomatoes, sliced
• 1 None small onion, finely diced
• 5 tbsp fresh basil leaves
• 1 None large, round flatbread, halved horizontally