How is signaling theory different from cue utilization theory?
I think you do mean cue utilization theory. According to the link provided in @NickJ's comment, and as far as economic theory goes, I'd say that cue utilization is basically a signaling story.

Putting "cues" on organic food products (e.g. the "organic" label, information on nutrition and natural content) amounts to a signaling act committed by the seller. Since the organic cues is less costly for the real organic food producers to produce (for instance, labeling non-organic foods as organic would face legal disputes, and hence a negative expected cost), these cues (or signals) are reliable.

Thus in principle, organic food sellers sending cues to consumers is no different from the classical signaling model where job seekers uses university degrees to signal their ability.