The spicy taste of many Korean foods - red pepper powder. Red Chili Pepperis made by drying Korean red chili peppers in the sun, de-seeding them and crushing them into flakes.
Best deal I could find on these. Ordered enough to get free shipping as well. Gave some to my mom, and she especially likes the lemon ones (so refreshing!). A little bit of a delay in shipping, due to labor shortage, but not bad at all. Will definitely order from again.