But they are every bit English, originating in the early-18th century. That they became "English" was to differentiate them from the more recent sweet cakey concoction that is also now called muffin.
In her cookbook, The Art of Cookery Made Plain and Easy, from 1747, Hannah Glasse offered probably the first recipe for muffins. They were not something that you would have found in most cookbooks aimed at upper class households as in earlier decades. Glasse’s cookbook was intended to be used by domestic staff.
Glasse’s recipe for muffins - “To make Muffins and Oat-cakes. To a Bushel of Hertfordshire white Flour, take a Pint and half of good Ale-yeast, from pale Malt if you can get it, because it is whitest; let the Yeast lie in Water all Night, the next Day pour off the Water clear, make two Gallons of Water just Milk warm, not to scald your Yeast, and two Ounces of Salt, mix your Water, Yeast and Salt well together for about a quarter of an Hour, then strain it, and mix up your Dough as light as possible, and let it lie in your Trough an Hour to rise, then with your Hand roll it, and pull it into little Pieces about as big as a large Walnut, roll them with your Hand like a Ball, lay them on your Table, and as fast as you do them lay a Piece of Flannel over them, and be sure to keep your Dough covered with Flannel ; when you have rolled out all your Dough, begin to bake the first, and by that Time they will be spread out in the right Form; lay them on your Iron, as one Side begins to change Colour turn the other, and take great Care they don’t burn, or be too much discolored; but that you will be a Judge off in two or three Makings. Take Care the middle of the Iron is not too hot, as it will be, but then you may put a Brickbat or two in the middle of the Fire to slacken the Heat. The Thing you bake on must be made thus. Build a Place just as if you was going to set a Copper, and in the Stead of a Copper a Piece of Iron all over the Top fix’d in Form, just the same as the Bottom of an Iron Pot, and make your Fire underneath with Coal as in a Copper; observe, Muffins are made the same Way, only this, when you pull them to Pieces roll them in a good deal of Flour, and with a Rolling-pin roll them thin, cover them with a Piece of Flannel, and they will rise to a proper Thickness; and if you find them too big or too little, you must roll Dough accordingly, these must not be the least discolored. And when you eat them, toast them with a Fork crisp on both Sides, then with your Hand pull them open, and they will be like a Honey-Comb ; lay in as much Butter as you intend to use, then clap them together again, and set it by the Fire, when you think the Butter is melted turn them, that both Sides may be buttered alike, but don’t touch them with a Knife, either to spread or cut them open, if you do they will be as heavy as Lead, only when they are quite buttered and done, you may cut them across with a Knife. Note, Some Flour will soak up a Quart or three Pints more Water then other Flour, then you must add more Water, or shake in more Flour in the making up, for the Dough must be as light as possible."
The cooking and texture is every bit the “English muffin”.
John Mollard in his 1802 cookbook, The Art of Cookery Made Easy and Refined, gives a recipe for muffin pudding – “Muffin Pudding with dried Cherries. To a pint and a half of milk add a few coriander seeds, a bit of lemon peel, sugar to the palate, and boil them together ten minutes. Then put four muffins into a pan, strain the milk over them, and, when they are cold, mash them with a wooden spoon; add half a gill of brandy, half a pound of dried cherries, a little grated nutmeg, two ounces of jordan almonds blanched and pounded very fine, and six eggs well beaten. Mix all together and boil in a bason, or bake it in a dish with paste round it.”
Illustration of a muffin man - https://collections.britishart.yale.edu/catalog/tms:12154
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