Q. Can one successfully make French toast with soy milk (beverage) rather than cows' milk?
Success being in the palate of the beholder yes you can. The milk in French toast provides moistness and flavor. It is the all-important egg that contributes structure and well, more flavor. If you are amenable to drinking soy milk, we see no reason that you can't use it in French toast.
Most of the soy milks we have come across lean towards sweetness a bit, anyway, so you may find it enhances your French toast. Friends may start asking you for your recipe....
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