Preheat oven to 425F.
Dice tomatoes, slice zucchini into ¼in round, halve ciabattas.
in a small bowl, combine 6 tbsp ketchup, 2 tsp vinegar
Heat oil in a large pan on med-high heat. add tomatoes, 4 tbsp water, 2 tbsp vinegar, and 1 tsp sugar. Season with
salt and pepper. Cook breaking up/mashing the tomatoes, until mixture is jammy 4-6 minutes. Transfer to small
dish, wash out pan.
While the jam cooks, toss zucchini in bowl with drizzle of oil, sprinkle with Italian seasoning and toss. Once jam is removed from pan, cook the zucchini until tender 2-4 minutes a side. transfer to a plate. While cooking in a small bowl combine mayo and garlic to taste (for sandwich spread- optional).
Spread mayo on one side of bun, spread tomato jam on the other side. Fill with layers of zucchini & mozzarella cheese. Add sandwich to pan to toast until the cheese is melted.
Tip: Wrap extras in tin foil, heat it up in a toaster oven/oven the next day!