Preheat the grill to high heat.
Place a cast iron skillet on a hot grill with 1 teaspoon of olive oil and caramelize the garlic. Once it’s brown add in the tomatoes, lemon zest and salt and pepper and let it stew on high heat for 10 to 12 minutes.
Add the salmon to a food processor and pulse until it becomes like a paste. From there transfer it to a bowl and mix with 1 egg, diced sweet onion, lemon juice, soy sauce, bread crumbs made from the dried out rolls, salt and pepper until combined.
Next form 4 patties, brush each side with the remaining olive oil, season again with salt and pepper and cook on a hot spot on the grill for 4 to 6 minutes on each side or until dark grill marks are formed and they are cooked through out.
Finish by placing a cooked salmon cake on top of a sliced roll and top off with a few tablespoons of the tomato-lemon sauce.