The best versions of patatas bravas showcase crispy, well-browned potatoes served with a smoky, spicy tomato-based sauce. To create an ultracrispy crust without the need for double frying, we first parboiled russet potatoes with baking soda, which triggers a chain reaction that causes the pectin on the exteriors of the potatoes to break down and release a substantial layer of amylose that, when fried, develops into a thick crust. We also tossed the parcooked potatoes with kosher salt, which roughs up the surfaces of the potatoes, creating many nooks and crannies through which steam can escape. As the steam escapes, the nooks and crannies trap oil, helping to make an even more substantial crunchy crust. For our sauce, we cooked tomato paste, cayenne, sweet smoked paprika, garlic, and water to make a smooth, smoky, and spicy mixture, finishing with sherry vinegar for tang. Finally, adding mayonnaise allowed us to combine the bravas sauce and another common accompaniment, alioli, into a single sauce.