A grilled sticky-rice sausage split open like a bun and filled with a grilled, sweet Taiwanese pork sausage, garlic, pickles and sauce. 大肠 and 小肠 (large and small intestine) here just mean the two sausages. A Taiwanese snack.
Lǎobǎn, gěi wǒ lái yí fèn dàchángbāoxiǎocháng jiā suàn.
Boss, one sausage-in-sausage with extra garlic, please.
Tips
culture
A signature Taiwanese night-market snack (台湾夜市): a grilled pork sausage tucked inside a split, grilled glutinous-rice sausage like a hot dog, then loaded with garlic, pickled radish, sweet soy, and chili. The name is literal - 大肠 'large intestine' (the rice sausage's casing) wraps 小肠 'small intestine' (the pork sausage).
memory
Read it left to right as a sandwich: 大肠 [包] 小肠 = 'big intestine wraps little intestine'. 包 here means 'to wrap', the same character as in 包子 (bāozi, steamed bun).