"Would you like anything with that?" This question, asked more often than you probably realise – virtually every time you order some kind of warm beverage, in fact – may well determine whether or not you've noticed them. Soft, sweeter than your average treat, frequently oozing with peanut butter or fudge, they have quietly marked out their glass-boxed territory, waiting to be chosen. Chosen, eaten, and turned into the Next Big Thing.
The rise of the American cake has been nothing if not determined. It started with the blueberry muffin (remember when they made their splotchy debut at your local Starbucks, little aliens with chicken pox?), moved on to the cupcake with all its girly Sex and the City allure, briefly took the form of red velvet, before embracing its current, super-sized incarnation: the Amish whoopie pie, a kind of spongy, marshmallowy, buttercreamy sandwich of a cake.
Or perhaps it wasn't the muffin at all. Perhaps it all began with the chocolate chip cookie and its many variants, which have proven so popular that recent reports suggest the Jammy Dodger may be in jeopardy. Or maybe it was the cheesecake, or the Krispy Kreme, or the pecan nut pie. Or the granola bar, or the brownie, or the Oreo. Who knows? One thing, however, is clear: the dainty sponge of British tradition has been usurped. In its place is the sticky, gooey, sugar-laden, American treat.
"It could be the frontier mentality," says Warren Brown, author of United Cakes of America, when I call to ask why, exactly, American confectionery is so, well, irresistible. Irresistible, and sweet and ... large. "In the US, we make everything bigger, with more sugar heaped in. It's just part of the culture of size equalling value for money."
Brown has spent much of his career travelling the country in order to source inspiration for his book, which boasts more than 50 recipes spanning its culinary geography. His favourites are the sweet potato cake and the Tennessee mountain stack cake, neither of which has made the journey across the Atlantic. Yet.
In a leafy corner of west London, a pair of American bakers are doing their best to bring more of their country's cakes to British shores. David Lesniak and David Muniz moved to the UK several years ago, opening Outsider Tart, a bakery, café and cookery school, last year. The name came from the two Davids' shared love of outsider art. They have already become poster-boys for the whoopie pie, with their velvet and chocolate marble varieties winning ecstatic reviews from bloggers and journalists. Now, in a hastily arranged cooking lesson, they are teaching me how to make their rather onomatopoeic "s'mores brownies".
"S'mores are a classic boy-scout snack," explains Muniz. "They're a campfire thing: two graham crackers – which is kind of like a digestive biscuit, but even better – with some melted marshmallow and chocolate in between." S'mores brownies, on the other hand, are very much an all-occasions thing, their consumption popular long after the promise to "be prepared" has been abandoned. They are also very, very delicious: biscuity and crunchy and crumbly and chocolaty. With a sort of cheesecake-esque base of crushed biscuits, the brownie bit forms the middle layer which is topped, finally, with a golden-white cloud of toasted marshmallows.
"People love these and they're not at all difficult to make," says Muniz of his creation. "One of the big things with American baking is that it is much, much less scientific than European traditions. A lot of the time it can be quite intimidating. If you're trying to do a fine pastry or a perfect sponge, you worry that a bit too much of this, or a bit too little of that, will ruin your whole dessert. But with the classic American goodies there is a lot of room for improvisation. You experiment, it might not turn out how you wanted, but you eat it anyway and you know what? It tastes pretty good."
This happy-go-lucky approach is quite apparent as we set about mixing our brownie batter, not least because I promptly dump half the dry ingredients in with the wet before realising that they were, in fact supposed to be separate. Remarkably sanguine, my tutors assure me it'll be OK. And guess what? It is. More than OK, if the groans of pleasure my brownies elicit amongst colleagues are anything to go by.
When I mention my newfound infatuation to chef Bill Yosses, he laughs. "There is a lot of that in the States: recipes that we grew up with as kids, which produce an almost visceral reaction. Why not make a great dessert with them, using better ingredients?" Yosses should know a thing or two about American tastes. When he's not discussing the delights of cake with British journalists, he is the executive pastry chef at the White House. Google him and you are immediately greeted with pictures of him laughing and joking alongside Michelle Obama or Hillary Clinton. His recent book, The Perfect Finish, provides a glossy tour of his country's confectionery. Chocolate chunk cookies with Nutella and Mamie Eisenhower's cheesecake sit alongside red eye devil's food cake and, somewhat thrillingly, chocolate caramel tart with sea salt – remember the flurry last year over salted caramels, rumoured to be the President's favourite sweet?
"To understand where all these dishes come from, you have to look at our traditions," says Yosses. "One of the sources I use is a website set up by Michigan University called Feeding America (Goo.gl/LeiU). It has scans of original cookbooks from 1650, with all the cooks' notes. It offers a real glimpse into life at the time. A lot of American cooking evolved as people moved here from all over and then adapted their dishes to the ingredients they could find. In New Orleans, for instance, you've got the French influence, the Native American influence, all sorts."
Back at Outsider Tart, with the s'mores brownies done and dusted, our attention turns to two other staples: the white chocolate blondies (just as foolproof: this time I managed to double the egg content; they still turned out to be delicious) and – joy of joys – velvet whoopies, in which we swirl red colouring for full-on patriotic effect. The whoopies are a delight to make: rather more time-consuming that the brownies, but tremendous fun in an all-hands-on-deck, baking-with-the-kids kind of way. Which, really, shouldn't be surprising: the "whoopie" in the pies' name stems from the cries of delight that could be heard in Amish households once children clapped eyes on the finished product.
The most fun, most satisfying part of all comes when we get to assemble our sandwiches. For icing we went for the modern cream cheese option over the more traditional cream or buttercream or the Southern marshmallow filling. Squidging it together (the trick is to squash, then twist), inspecting for symmetry, then getting to take a soft, cream-and-cake-filled bite is, well, enough to make you cry "whoopie". Almost.
David Lesniak and David Muniz are working on a cookbook to be published in June next year
'The Perfect Finish: Special Desserts for Every Occasion' by Bill Yosses and Melissa Clark is published by Norton, £25
'United Cakes of America' by Warren Brown is published by Stewart, Tabori & Chang, £19.99
Outsider Tart S'mores Brownies
For the crust:
11/3 cups graham cracker (or digestive) crumbs
1tbsp light brown sugar
4oz unsalted butter, softened
2tbsp all-purpose flour
For the filling:
12oz light brown sugar
Cup graham cracker/digestive crumbs
1tsp baking powder
1tsp vanilla extract
2 large eggs
Cup of chocolate chips of your choice
Cup chopped pecans or more to taste (optional)
For the topping:
Miniature marshmallows as desired
Preheat oven to 350F. Butter and line a 9in x 9in x 2in baking pan, dusting the sides with flour and tapping out any excess.
For the crust, combine the crumbs, sugar, butter and flour in the bowl of an electric mixer until moist and crumbly. Dump the mixture into the prepared pan and press it into the bottom and up the sides of the pan. Bake about 15 minutes or until lightly toasted.
For the filling, in the previously used bowl, combine all the ingredients except the chocolate chips and nuts. Mix on medium-low speed until well blended. Remove the bowl from the mixer and fold in the chocolate chips or nuts or both. Pour the filling over the cooled crust and spread until smooth.
Bake the brownies for another 20 to 25 minutes or until set. Remove from the oven and cover the top of the brownies with miniature marshmallows. Return to the oven for about 5 minutes or until the marshmallows melt and become golden. Cool the brownies before cutting into squares.
OVER HERE – THE US CAKE INVASION
The blueberry muffin: c1990s
Quite different from the buttery, tea-time English version this all-American creation is the official culinary symbol of Minnesota. Its encroachment on the English muffin's linguistic territory caused confusion as the immigrant slowly rose up café menus. Order a muffin now and it's more likely to be American than anything else.
Red velvet cake: c2007
Cooked correctly, the red velvet cake is breathtaking: silkily soft, given a pudding-like texture by the inclusion of buttermilk with a rich, white icing. Featured in the 1980s film 'Steel Magnolias', and served at singer Jessica Simpson's wedding, red velvet was named "the cake to stop traffic" by the 'New York Times' in 2007. Its freeze-frame effect rapidly crossed the Atlantic.
Magnolia cupcakes: c2009
When Carrie Bradshaw and pals gave the Magnolia Bakery's pretty little creations their seal of approval, the cupcake's fortunes were sealed. Cupcakes became the sweet to be seen with in 2009, spawning a host of trendy British cupcake shops. Like the American muffin, they have come to eclipse the more modest British fairy cake.
Whoopie pies: c2010
Proclaimed the "dessert of 2010" by trendsetters across the board, the whoopie pie has made its debut at Harrods, Selfridges, Marks & Spencer and – of course, Outsider Tart. Oprah famously endorsed it, which may give a clue as to the source of its popularity.
S'mores brownies for 2011?
Not a trend over here – yet. S'mores brownies have become the thing to serve at Fourth of July parties across America, seen as a more adult version of the childhood S'mores. Purveyors of mini marshmallows, be warned.