Adding sugar is a must, but should you boil your sweet potatoes or bake them?
And are eggs essential? Then there is the dilemma over toppings. Marshmallows,
anyone?
Perfect
sweet potato casserole. Photograph: Felicity Cloake for the Guardian
When I asked an American friend what people do to celebrate Thanksgiving, he
said that, mostly, they ate. And when they weren’t eating, they were watching
football. No church, no gifts, just good food and thankfulness.
And what food! Deep-fried turkeys and pumpkin pies, cornbread stuffing and
cranberry relish – and (most exotic of all to these British eyes) candied sweet
potatoes, a dessert that has somehow fought its way on to the main course of the
biggest meal of the year. Though the sweet potato has been an important part of
the continent’s diet for millennia, and early European settlers readily adopted
it as a pie filling, the Thanksgiving casserole’s infamous marshmallow topping
didn’t appear until the early 20th century, apparently at the behest of
interested candy manufacturers.
Sugar and gravy might not be a combination that every American is thankful
for, however – Jane Nickerson, writing in the New York Times in 1948, prefaces
her recipe with the underwhelming declaration: “I am not a fan, but about
250,000,000 Americans are, so here is my faint nod to their mystifying tastes.”
I’m going to out myself – this week I discovered that, though I’m not American,
I am a bit of a fan of candied sweet potatoes. Which just goes to show that you
should try something before you knock it. Cooks
Illustrated’s candied sweet potato.Photograph: Felicity Cloake/Guardian
The potatoes
Like most tubers, the dense sweet potato requires some serious cooking. Early
recipes often boil them in their skins, something also advocated by the classic
Joy of Cooking, but the Cook’s Illustrated All-Time Best Recipes warn that this
yields a wet texture and a “mild, watery flavour”. They’re right; the Joy may be
a bible of American cooking, but its sweet potatoes remind me of boring old
boiled carrots.
Instead, Cook’s Illustrated braises the potatoes in a mixture of cream,
butter and sugar while Chow goes for a sugar syrup and butter mixture instead –
both using just enough liquid to cook the vegetables through, but not enough to
wash out their flavour. The Cooks Illustrated version, which eschews water
altogether, is better, but it’s still not as good as the baked varieties I
try.
Saveur and Southern Living magazines both bake their sweet potatoes in their
skins before peeling and mashing them. If you can afford the power, this method
yields an intensely sweet, full-flavoured result; sweet potatoes that taste
almost ridiculously of themselves. Chow and Joy of Cooking both serve their
sweet potatoes in slices, rather than mashing or puréeing them, as other recipes
suggest. I think this is a mistake; one of my favourite things about this tuber
is its velvety texture when puréed. This also means that the Chow version hasn’t
absorbed much of the buttery, sugary flavour of its braising liquid, remaining
sweet potato chunks in sauce. Far less satisfactory. Saveur’s
sweet potato casserole.Photograph:
Felicity Cloake/Guardian
The fats
Butter is obviously a must here – you can’t have mashed potato of any stamp
without it. Southern Living adds milk too, but as it’s a special occasion, I
prefer the thicker double cream in the Saveur and Cook’s Illustrated recipes.
Saveur and Southern Living also beat in eggs. I’m sceptical; as with the milk, I
feel the less water in this casserole the better, but the eggs do give the
filling a rich, almost custardy texture. To be safe, I decide to use just the
yolks – you could even use the whites for a meringue topping if you’re feeling
adventurous, but I’d save them for a puritan post-Thanksgiving breakfast.
The flavourings
Attempt to put a sugar-free sweet potato casserole on the table on
Thanksgiving of all days, and you might just have your green card revoked;
absolutely everyone adds some. But you don’t have to pour in a whole cup of the
stuff, like Southern Living – it’s quite acceptable to stick with a more modest
teaspoon, as Cook’s Illustrated suggests, just to accentuate the tuber’s natural
sweetness. That said, I’m not going to stop you if you want to go mad on
thankfulness for sugar once a year. The Joy of
Cooking’s sweet potato.Photograph:
Felicity Cloake/Guardian
Chow and Saveur use dark brown sugar, Joy goes for the simple brown stuff,
and no one else specifies, so I use white. As with the pumpkin pie, the more
caramelised flavours of the less refined sugars are lovely in combination with
the vegetable star, making it taste far more festive, and interesting, than
ordinary caster.
Holiday or not, I draw the line at too many spices; the nutmeg, vanilla and
cinnamon in the Saveur pie completely overwhelm the poor old potato. The warmth
of its grated ginger is inspired, however – much fresher than Joy’s powdered
variety or Chow’s crystallised version. That, and a sprinkling of nutmeg, is
quite enough for me, though I’d also accept the merest pinch of cinnamon, given
the American fondness for the stuff. Joy is the only recipe to balance the sugar
with lemon juice – it works because of the ridiculous amount of sugar it uses,
but my more restrained recipe renders such an addition unnecessary. Southern
Living’s sweet potato casserole.Photograph: Felicity Cloake/Guardian
Toppings
I have to admit, marshmallows aren’t really my thing outside a Wagon Wheel,
but I do like the crunch of the various other toppings the recipes use. Joy goes
for a simple brown sugar glaze while Saveur makes an oat and brown sugar crumble
with chopped pecan nuts, which, though delicious, I find a bit heavy for a side
dish. Southern Living’s crushed cornflakes go down surprisingly well, but in the
end, I settle for a classic pecan praline, on the basis that, as I’ve reined
back the sugar in the dish itself, I can afford a little on top.
It is Thanksgiving, after all. Whether you crown it with a whole heap of pink
and white marshmallows is up to you. (serves 4-6) 900g sweet potatoes 45g butter 1 egg
yolk 2 tbsp double cream 1 tsp dark muscovado sugar 1 tsp grated
ginger Sprinkling of nutmeg ½ tsp salt For the
topping 15g dark muscovado sugar 2 tbsp flour 1 tbsp butter,
melted 40g pecans, roughly chopped
Heat the oven to 220C/gas mark 7 and prick the sweet potatoes with a fork.
Bake until soft – how long this takes will depend on the size of your sweet
potatoes, but check after 45 minutes.
Turn the oven down to 180C/gas mark 4. When the potatoes are cool enough to
handle, peel off the skins and put the flesh into a bowl and mash until smooth –
or use a stick blender. Add the butter and beat in until melted, then beat in
the remaining ingredients. Taste for seasoning.
Spoon into an oven dish. Mix together all the topping ingredients with a
pinch of salt and sprinkle over the top of the potatoes. Bake for about 25
minutes until the topping is crunchy and brown.
Candied sweet potatoes – the king of the Thanksgiving table, or a sugary
distraction from good honest mash? Are you a marshmallow fan, or does the very
idea of serving them with gravy turn your stomach? And, for those celebrating
Thanksgiving, what else will you be serving
up?
