Korean Sweet Potato Casserole Recipe: Roasted Goguma With a Pecan and Sesame Crumble for Thanksgiving

The sweet potato casserole is having a quiet makeover, and the person changing it is the host under 30. USA Today reported on 4 November that Gen Z cooks are keeping the Thanksgiving staples but adding global flavours, and it described the Las Vegas cook and author Jessica Woo adding Korean sweet potatoes to her sweet potato casserole. This recipe takes that swap and builds a full dish around it.

The timing suits the table. In a survey from Campbell's, reported by Sporked on 7 November, 65 per cent of Gen Z respondents said they would happily eat a Thanksgiving dinner made entirely of sides, and sweet potatoes ranked third among all respondents' favourite sides, behind green bean casserole and mac and cheese.

Korean sweet potatoes, goguma, are the point. They have purple-red skin and pale golden flesh, and when roasted whole they turn dense, sticky and almost caramel-sweet, the way the street-vendor gun-goguma sold from drum ovens every winter in Korea does. That sweetness means you need far less sugar than the old marshmallow version, a topping that The Takeout traces to a 1917 Angelus Marshmallow pamphlet promoting the product. Wikipedia notes that softer, moister types are preferred for roasting, so choose the softer-fleshed goguma if the market offers more than one kind.

Ingredients

Serves 6 to 8 as a side. Total time about 2 hours, mostly hands-off roasting.

• 1.2 kg Korean sweet potatoes (goguma), scrubbed
• 50 g unsalted butter, melted
• 80 ml whole milk
• 2 large eggs
• 60 ml maple syrup
• 1 tsp vanilla extract
• 1/2 tsp ground cinnamon
• 3/4 tsp fine salt
• For the crumble: 80 g pecans, roughly chopped
• 50 g plain flour
• 50 g light brown sugar
• 40 g cold unsalted butter, diced
• 1 tbsp black sesame seeds
• Pinch of salt

Method

1. Heat the oven to 200 C (180 C fan). Line a baking tray with baking paper, because the sugars will leak and burn onto bare metal.
2. Prick each sweet potato a few times with a fork and set them on the tray. Roast for 45 to 60 minutes, turning once, until they slump when squeezed with a cloth and syrup is bubbling at the holes.
3. Cool the potatoes for 10 minutes, then peel off the skins. Weigh out about 800 g of flesh into a large bowl and mash it with a fork or masher until mostly smooth. Reduce the oven to 180 C (160 C fan).
4. Whisk the melted butter, milk, eggs, maple syrup, vanilla, cinnamon and salt together in a jug, then fold into the mash until combined. Goguma is drier than orange sweet potato, so the mixture should look thick but spoonable.
5. Scrape the mixture into a lightly buttered 20 cm square baking dish or a 1.5 litre casserole and level the top.
6. For the crumble, rub the flour, sugar, cold butter and salt together with your fingertips until it looks like coarse breadcrumbs, then stir in the pecans and sesame seeds.
7. Scatter the crumble evenly over the sweet potato without pressing it down.
8. Bake for 30 to 35 minutes, until the centre is just set and the crumble is deep golden. If the pecans darken too fast, tent loosely with foil.
9. Rest for 10 minutes before serving, which lets the custard firm up enough to scoop cleanly.

Tips, swaps and storage

If you cannot find goguma, use the similar Japanese satsuma-imo, or orange sweet potatoes, though the orange types are wetter and less sweet. In that case roast them well and cut the milk to 60 ml.

Taste the mash before the eggs go in: it should be pleasantly sweet, with enough salt that it does not taste flat. The roasted mash can be made up to two days ahead and kept covered in the fridge. Add the egg mixture and the crumble just before baking, and allow 10 minutes more from cold. Leftovers keep for four days in the fridge and reheat at 160 C for about 15 minutes. For a savoury edge, stir a spoonful of white miso into the butter before mixing.

Thanksgiving falls on 26 November this year, so there is time to test it once on a weeknight. If it works, the unmarshmallowed, nuttier casserole may be the one the table asks for again.