Custom "ingredients" box within a recipe post

I’m not sure what I am looking for, so apologies if others have answered this.

I have a cooking blog to which I will be posting many recipes. Every recipe will have an ingredients list. I want this list to appear within the content of the recipe.

The ingredients will be in a box and will have its own styling different from the default styles for the post content. See here for an approximation of what I mean:

https://www.el-cordovez.com/clients/sample_recipe/index.html

So what is the best way to create a way to input this list every time I create a new “recipe” post?

Ideally, I imagine, it would be useful to see under “Add another post” a second input area that would allow me to put the ingredients, select their own formatting by showing formatting options for the text.

Doable? I would prefer not to use a plug-in if this is not master level programming technique, because I would actually like to learn to do this. But if it is too much hassle, a plug-in would be fine too.