To hard-boil the eggs, place the eggs in a small saucepan and cover with water. Bring to a boil over medium-high heat, then cover the pan and turn off the heat. Allow the eggs to sit for 9 minutes. Drain and shock in ice water. Now they are ready to use. To make the crostini, brush sixteen 1/4-inch-thick baguette slices with extra-virgin olive oil, and sprinkle with kosher salt. Bake in a 400-degree oven for about 5 minutes, rotating halfway through.