COSRX
COSRX is Korean brand that focuses on using simple formulations and delivering highly effective products. Their most popular product is, without a doubt, the Advanced Snail 96 Mucin Power Essence. It is even used by the Hollywood elite such as Emily Ratajkowski - she swears by it!
If you're looking to dabble in K-Beauty and not sure where to start, COSRX as a brand is a great place to start.