Salt-and-pepper shrimp is a beloved Cantonese dish that combines golden, crispy fried shrimp with an aromatic salt-and-pepper seasoning. This version adds a rather unexpected character to the party: precooked polenta. Yes, those long tubes of polenta stashed near the dried pastas in grocery stores you never know what to do with transform into crispy, golden cubes that bulk up the stir-fry and turn this quick recipe into a hearty dinner. The trick is to cook them in a nonstick pan, allowing them to morph into golden brown cubes that are crunchy on the outside and creamy on the inside. Pairing the cubes with crisp shrimp, green onions, and chiles, then showering everything in a generous mixture of salt, sugar, black pepper, and Sichuan peppercorns.