If utility class is an anti pattern, what is the alternatives in PHP?

I am trying to build my own MVC framework (of course to learn it better) by following latest OOP design pattern. I was wondering, what is the best practice for placing repeatable codes (which are used to stay in the utility classes as static methods, which is consider not a good patterns).

For example, we want to traverse an multi dimensional array using dot separated string, and I have to utilize this algorithm in several classes (which are subclasses from other base classes). How can I do that without using utility class and without repeating the same code multiple times?