Preheat the oven to 200C fan-forced (220C conventional). Add the tomatoes, kimchi, sugar, sesame oil and soy to a deep roasting tin. Season with pepper and toss together. Place in the oven and roast for 20 minutes, or until the tomatoes are tender and juicy. Add 2 cups of boiling water and roast for a further 10 minutes.
Set the tray aside to cool slightly. Transfer the tomatoes to a saucepan and, using a hand-stick blender, blitz until smooth. Place over low heat and keep warm.
Meanwhile, place half the bread slices on the bench. Spread with gochujang, top with cheese and sandwich with remaining bread. Spread the outsides of each sandwich with butter.
Heat a large non-stick frying pan over medium heat. Add the sandwiches and toast for 2-3 minutes each side or until the bread is golden and cheese has melted.
Serve soup with toasted cheese sandwiches and extra pepper.
