I've been making Knox blox with soy milk. I make a small recipe:
1/4 c soy milk..........30 cal
1 pkt Knox gelatine....10 cal
3/4 c boiling water......0 cal
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40 cal per recipe
40 calories for the whole dish shown below. They set up well. I dice them for Pip but you could make a bigger recipe and cut them into cubes.