Pre-heat oven to 125°.
Slice the Brussels sprouts in half, then place flat side down on cutting board, julienne into super thin strips, 1/16 to 1/8 inch wide.
Toss sprout strips with olive oil to lightly coat. Spread on a baking sheet lined with parchment.
Place in oven overnight.
Remove and toss crispy Brussels sprouts with salt and serve in place of shoestring potatoes as a crunch snack or topping for soup or entrée.