Zucchini weenie panini sandwich (from Bob's Burgers)

Ingredients

• 1 pound Roma tomatoes, diced (4 to 6 tomatoes)
• 1/4 teaspoon kosher salt
• 1/4 teaspoon celery salt
• 1 tablespoon brown sugar
• 1/4 teaspoon onion powder
• 1 teaspoon black pepper
• 1/4 cup balsamic vinegar
• 1/4 white or yellow onion, diced (add at very end)
• 6 tablespoons mayonnaise
• 2 tablespoons crushed Calabrian chilis
• 1 hot dog or fully cooked brat or sausage
• 1 teaspoon olive oil
• 3 or 4 quarter-inch thick slices of zucchini (enough to make a single layer on your bread)
• Cajun seasoning (or just salt and black pepper)
• 1 Ciabatta roll or French sandwich roll
• Calabrian chili mayonnaise (from above)
• 2 to 3 ounces shredded mozzarella cheese (can use provolone, Monterey Jack or any other shredded cheese)
• Zucchini slices (from above)
• Weenies (hot dogs from above)
• tomato and onion jam (from above)
• 1 tablespoon butter