Reasonably fresh whole wheat spaghetti should not take 15 minutes to cook. I would suspect that it might be very old. Whole wheat pasta will take a few, 2 to 4, minutes longer to cook to al dente, than white pasta. I normally cook the spirals, not sphagetti, and the spirals take 9 to 10 minutes to cook. I use my ww lasagna oncooked in casseroles, so that avoids the whole issue!
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