Preheat oven to 425 degrees. Arrange bread on a baking sheet and lightly brush with olive oil and sprinkle with salt. Remove both ends from the onion; cut the onion in half and slice thinly into half moons and separate pieces. Remove woody ends from asparagus and then cut each piece in half on a bias. Heat a medium sized cast iron pan to medium with 1 tbsp olive oil. Add onion, sprinkle with salt and sauté until the onions are translucent and beginning to turn golden brown about 7 minutes. Transfer from pan until ready for serving. Add an additional tbsp of olive oil to the pan; add asparagus; salt lightly. Sauté on medium for 7-8 minutes until al dente and slightly golden brown. Bake crostini for 10 minutes until golden brown. Remove from oven and layer a few slices of parmesan cheese (we used a vegetable peeler to slice it nice and thin), add a layer on onion, top with pan seared asparagus, and drizzle with fig balsamic.  Enjoy!