1. Toast the bread in a cast-iron skillet, under the broiler, or on the barbecue until golden brown.
2. Rub each slice firmly with a garlic-half, being careful to not rip bread.
3. Divide tomato onto the 4 slices of bread, pressing down as you spread it so the bread absorbs the liquid.
4. Drizzle each slice with olive oil and add a pinch of fleur de sel.
5. Add a little lemon zest onto each slice, if using.
6. Serve immediately.

NOTE

Ideally use a fresh tomato. If necessary, you can replace it with 125 mL (½ cup) canned, diced tomatoes.