- 4½-inch-thick slices from a bâtard (or 8 slices from a baguette or 2 slices from a large round rustic white loaf, cut in half)
- Extra-virgin olive oil, for brushing the bread
- 1 garlic clove
- 3 tablespoons salted, Europeanstyle butter, softened just to a spreadable (not oily) consistency
- 1/8 small red onion, cut through the core and thinly sliced (about 40 slices)
- 4 fillets canned smoked sardines, backbones removed
- 24 stems pepper cress or live watercress
- Sea salt
- Adjust the oven rack to the middle position and preheat the oven to 350°F.
- Place the bread slices on a baking sheet, brush the tops with olive oil, and bake them for 15 to 20 minutes, until they’re lightly toasted and golden brown. (You can also toast the bread in a toaster, but without the oil. Then brush the toast with oil after they’re done.) Rub the oiled side of the crostini with the garlic and set them on your work surface, oiled side up.
- Spread about 2 teaspoons of butter in an uneven layer on each crostino, leaving the edges of the bread visible. Scatter the onion slices over the butter, dividing them evenly, lay 1 sardine on each, and top with the cress and a few grains of sea salt.