Kale is a leafy green vegetable known for its slightly bitter taste, which can be attributed to the presence of heart-healthy compounds called glucosinolates. When baking kale, some of its signature bitterness will transfer to the chips. However, you can avoid harsh, bitter flavors by removing the chips from the oven before they brown too much. Slight browning around the edges adds a nice flavor, but be careful not to let the chips become burnt.