There are many bases you can use for crostini, but the one I turn to most is made from a baguette. You slice the baguette 13mm (1/2") thick, brush on some olive oil, and toast until they just start to turn brown. When done right, they have a great crunch on the outside with a soft, chewy interior.
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Preheat an oven or toaster oven to 200°C (400°F).
Cut the baguette into slices about 13mm (1/2") thick and lay them out on a baking sheet. Lightly brush on some olive oil and sprinkle with salt. Place in the oven and bake until just beginning to brown and crisp, about 7-10 minutes. Remove from the heat and let cool.