First I dice the tomatoes (leaving excess juice behind on the cutting board helps), then I stir in the salt. I add chopped onion, basil, and garlic, and let the mixture sit for a while to marinate, so the flavors mingle.
I slice the baguette diagonally into about ½-inch pieces, brush both sides with olive oil, then bake at 450°F until each slice is crisp and golden (usually 6-9 minutes).
Just before serving, I drain any excess tomato juice (so bread doesn’t get soggy), mix in the remaining olive oil, and adjust salt. I spoon the tomato salad onto the crisp toasts, drizzle thick balsamic vinegar over, and finish with flaky salt if I have it.