However, this phrase is a bit more nuanced than a simple literal translation suggests. Here's a more accurate interpretation:
"I love you, you goofball."
This captures the affectionate tone of the phrase. "Chato" can be translated as "annoying," but in this context, it's more like a playful term of endearment, similar to "goofball" or "dork."
It's important to consider the context of the conversation and the relationship between the speakers when translating phrases like this, as the intended meaning can be quite different from the literal translation.