May not be specifically for just banchan recipes, but this may be of interest to you. I requested it for a birthday gift coming up soon after hearing a lot of good things. Korean Home Cooking
If anyone wants a good Korean cookbook, I've really enjoyed Korean Home Cooking by Sohui Kim, it's got a lot of delicious recipes and really tries to present Korean cuisine as it is cooked and enjoyed in Korea by regular Koreans, rather than what Americans think of when they hear "Korean". For example, there are KBBQ recipes, but they are far from the focus and she describes how KBBQ is like a special-occasion thing there, not what people eat on a regular basis. I particularly like the soups and stews
So many people recommended it, and I received it for my birthday recently, the Korean Home Cooking is amazing!
Is it this one?
Sohui Kim - Korean Home Cooking: Classic and Modern Recipes
https://www.amazon.com/Korean-Home-Cooking-Classic-Recipes/dp/1419732404
I love the cookbook Korean Home Cooking and Maangchi’s cookbook as well. Those have both been good. Korean Home Cooking Maangchi’s Cookbook
Links are to Amazon but buy from your local bookstore if you can!