It is well documented that Franklin was interested in tofu, which he called a sort of cheese made from beans, and he got a recipe for making it that he sent on to others. But no source that I have found gives any reason to believe he or any of the others ever made any tofu. Does anyone here know of evidence on the question?
Probably not. It's impossible to prove a negative like this, so this answer is necessarily inferential.
Let's start by looking at Franklin's letter:
Benjamin Franklin to John Bartram London, Jan. 11, 1770.
My ever dear Friend:
I received your kind letter of Nov. 29, with the parcel of seeds, for which I am greatly obliged to you. I cannot make you adequate returns, in kind; but I send you . . . Chinese Garavances, with Father Navarretta’s account of the universal use of a cheese made of them, in China, which so excited my curiosity, that I caused inquiry to be made of Mr. Flint, who lived many years there, in what manner the cheese was made; and I send you his answer. I have since learnt, that some runnings of salt (I suppose runnet) is put into water, when the meal is in it, to turn to curds.
I think we have Garavances with us; but I know not whether they are the same with these, which actually came from China, and are what the Tau-fu is made of. They are said to be of great increase.
In the bolded passage, Franklin reveals that he has not successfully grown anything from the soybean seeds he has forwarded along. He calls them "Chinese Garavances," and says he doesn't know whether they differ from ordinary Garavances. This means he thinks soybeans are like chickpeas/garbanzo beans (though to be fair, he doesn't seem familiar with chickpeas either). But when he says that soybeans "are said to be of great increase," this implies a lack of firsthand experience with growing soybeans. No soybeans, no tofu.
He also implies a lack of experience with making tofu when he writes "some runnings of salt (I suppose runnet) is put into water." This is Franklin's sole commentary on the tofu recipe, which he otherwise forwarded to his friend unaltered. Franklin writes more authoritatively when describing recipes for dishes he probably has made (e.g. "Bite of a Mad Dog").
If you follow the link above, you can read the original recipe from James Flint. Flint also implies that he has never tried to make tofu himself: "The method the Chinese convert Callivances into Towfu. They first steep the Grain in warm water ten or twelve Hours to soften a little, that it may grind easily . . . Then they stir up the flower & put the Water over the Fire just for it to simmer . . . This is the process as I always understood."
So Franklin is playing a game of telephone with tofu recipes.
Also note that Franklin makes no mention of tofu's taste. In his other writings on food, he does mention taste:
We have an Infinity of Flowers, from which, by the voluntary Labour of Bees, Honey is extracted, for our Advantage. … Bread and Honey is pleasant and wholesome Eating. ‘Tis a Sweet that does not hurt the Teeth. How many fine Setts might be saved; and what an infinite Quantity of Tooth Ach avoided! (B. Franklin, Poor Richard Improved, 1765)
And on maize:
the Ears boil’d in their Leaves, and eaten with Butter are also good and agreeable Food. The green tender Grains dried, may be kept all the Year, and mix’d with green Haricots also dried, make at any time a pleasing Dish. (B. Franklin, On Mayz, ca. April 1785, unpublished)
And on American cuisine in general:
“Pray let me, an American, inform the gentleman, who seems ignorant of the matter, that Indian corn, take it for all in all, is one of the most agreeable and wholesome grains in the world; that its green leaves roasted are a delicacy beyond expression; that samp, hominy, succotash, and nokehock, made of it, are so many pleasing varieties; and that johny or hoecake, hot from the fire, is better than a Yorkshire muffin – But if Indian corn were so disagreeable and indigestible as the Stamp Act, does he imagine that we can get nothing else for breakfast? – Did he never hear that we have oatmeal in plenty, for water gruel or burgoo; as good wheat, rye and barley as the world affords, to make frumenty; or toast and ale; that there is every where plenty of milk, butter, and cheese; that rice is one of our staple commodities; that for tea, we have sage and bawm in our gardens, the young leaves of the sweet hickery or walnut, and above all, the buds of our pine, infinitely preferably to any tea from the Indies … Let the gentleman do us the honor of a visit in America, and I will engage to breakfast him every day in the month with a fresh variety.” (January 2nd, 1766, Benjamin Franklin)
Of course, none of this is definitive. Maybe at some point Franklin or his friend Bartram did try out the tofu recipe. If so, as the writer at the link says, it was probably more a science experiment than anything: "Without any cultural context for the food, 18th c. Philadelphians would have had little idea how to cook, season, store or eat tofu." Imagine thinking that tofu was going to be some kind of cheese. Having made it poorly from a third-hand recipe, you then spread it unadorned on a cracker or piece of toast. I imagine you wouldn't repeat the experience.
Bonus Ben Franklin Fact: He was into electrocuting turkeys because it made them "uncommonly tender."
Two nights ago being about to kill a Turkey from the Shock of two large Glass Jars (Leyden Jars), containing as much electrical fire as forty common Phials, I inadvertently took the whole thro’ my own Arm and Body.” (Benjamin Franklin)