What supplemental food, mimicking high-energy insect matter, might occasionally attract a Kinglet to a feeder?

Answer

Suet cakes, especially those containing peanut butter or finely ground nuts

To mimic high-energy insect matter, offering suet cakes that include peanut butter or finely ground nuts in a wire mesh feeder can sometimes work.

What supplemental food, mimicking high-energy insect matter, might occasionally attract a Kinglet to a feeder?
foodbirdKinglet