Awesomesauce is an informal term describing someone or something asextremely good or excellent.

Awesomesauce(超赞的、棒呆的)是种非正式用语，用于形容某人或某事物特别棒或极好的。新东方托福网络课程

If you want to describe something as excellent, you can use awesomesauce;on the other side of the coin, anything of a poor or disappointing standard isweak sauce. Weak sauce came first, and has a comprehensible origin as ametaphor; an inadequate sauce would certainly let down an otherwise decent meal.Though awesomesauce clearly comes from the words awesome and sauce, the formeris currently beating the latter in the Oxford English Corpus and Oxford TwitterCorpus.

如果你想形容一样东西很棒，你可以用“awesomesauce”;相反，很差劲、令人失望的东西就是“weak sauce(弱酱)”。先出现的是“weaksauce(弱酱)”，这个词是个来源很好理解的比喻：酱汁不够好肯定会让美食变味。虽然“awesomesauce(赞酱)”明显是“awesome(很赞的)”和“sauce(酱汁)”组合起来，但它现在已经在牛津英语语料库和牛津推特语料库把“弱酱”打败了。

For Example：

Seeing them perform live was awesomesauce!

能看他们进行现场表演真是棒呆了!