"Banana chocolate" refers to the combination of two flavors - banana and chocolate. It could describe a food or dessert that has both banana and chocolate ingredients or tastes, such as a banana chocolate chip muffin or a chocolate-covered banana.
I almost always bake something, and even though I've made banana chocolate chip muffins I wanted to make a different version. (slim-shoppin.com)
And since I don't get the opportunity very often — I figured I'd go all out and make banana chocolate chip pancakes. (justsotasty.com)
These tender vegan banana chocolate chip muffins are studded with rich chocolate chips, crunchy walnuts, and flavored with a hint of cinnamon. (connoisseurusveg.com)