I need to make more suet. Most of mine is being eaten out of the bedroom window by the Red-bellied Woodpeckers who are taking it to the nest. Soon they will bring the young over to feed themselves at the "food source".
I have helped raise a lot of birds over the years with this healthy snack:
-peanut butter (crunchy)
-corn meal
-flour
-lard

Melt the lard and peanut butter (now in plastic jars) in the microwave.
pour in big pot, raise temp to 150+ and stir in corn meal and flour.
When it cools, it hardens. I use more meal and flour in Summer and less in Winter so it will not melt in the feeder.
This is not as good as live bugs, but a substitute birds who prefer insects take to with gusto.

Many birds don't eat seeds.
Here are a couple "suet eaters" eating today near the CatBird seat:

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Downy Woodpecker

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White-breasted Nut Hatch

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Chickadee waiting her turn

My many Cardinals have also developed over the years into suet eaters. They love it!