Don’t do this folks, etrogim are intensively sprayed to keep away citrus scale (an insect that latches to the skin and exudes a protective shell.) There is no telling how much pesticide leaches into the fruit and pith. I have seen pumpkin sized Teimani etrog sold for its vegetable use. They are not that pretty on the outside.
Frumguy, if you etrog tastes horrible raw or cooked, you should be choshesh that you etrog in not the fruit mentioned in the Mishna Sukkah 4:2 that on the seventh day the children threw down their lulavim and ate their etrogim. The Teimani is edible as is, and the yanaver has a small and tastey fruit center, as did the infamous Corfu. From coins of Bar Kochva, and other period art, it would seem the original etrog was a squat fruit with a very elongated pitom.
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