In a pot, dissolve 1/2 cup of the salt in the water. Submerge the chicken in the brine; refrigerate overnight.
Drain and rinse the chicken. Rinse out the pot. Add the buttermilk and Tabasco, submerge the chicken in the buttermilk and refrigerate for 8 hours or overnight.
In a shallow bowl, mix the flour, baking powder, garlic powder, Old Bay, cayenne, black pepper and the remaining 1 teaspoon of salt. Shake the excess marinade off the chicken, then dredge in the flour. Dip the chicken back into the buttermilk and coat again in the flour.
Meanwhile, in a large cast-iron skillet, heat 1 inch of vegetable oil to 375°. Fry the chicken in batches until golden and cooked through, about 6 minutes per side. Drain on paper towels and serve.