Preheat your oven to 450°F or prepare a gas grill. If you prefer easy cleanup, line a large baking sheet with parchment paper. If your baking sheet is on the smaller side, you may need to bake in two batches.
Slice the baguette diagonally into pieces approximately ½-inch thick. You should be able to fit around 20 to 24 slices on a large baking sheet; any extra bread can be saved for another use. Lightly brush both sides of each slice with extra-virgin olive oil, which should require around 2 to 3 tablespoons.
Arrange the slices in a single layer on the prepared baking sheet and place them on the middle oven rack. Bake for 6 to 9 minutes, or until the crostini are crisp and a lovely golden color on the top. Lightly sprinkle with salt immediately after removing from the oven.
Transfer the baked crostini to a serving platter and serve as desired, or use them as a base for your favorite toppings.