Makes 4 servings
You could probably just lick this miso-maple jam off a spoon and be happy, but happiness is multiplied manyfold when you spread it generously over steaming-hot sweet potatoes. The jam, a mix of melted butter, miso, maple syrup, Sriracha and ready-made ponzu sauce, is just a touch sweet; mainly it’s spicy, salty and, because of the miso, hard to describe, as so many umami-rich foods are. If you like the jam as much as I do, keep some in the fridge to use on roasted carrots or squash, steamed cauliflower or seared salmon, halibut or scallops.
a word on the potatoes
The jam will be luscious on any type of sweet potato — it’s not bad on white potatoes either — but my preference is for Garnet sweet potatoes. You could use Japanese yams — the ones with white flesh — but they’re so inherently sweet that they tend to mute the complexity of the jam.
Working Ahead
The jam can be made up to 3 days ahead and kept tightly covered in the refrigerator.
Center a rack in the oven and preheat it to 400 degrees F. Line a baking sheet with foil.
Using a paring knife, poke a few holes in each potato. Place the potatoes on the baking sheet and roast for about 1 hour, until they give when prodded or squeezed.
Meanwhile, melt the butter in a small saucepan over low heat. Turn off the heat and gently whisk in the miso until fully incorporated. Whisk in the maple syrup, ponzu, ¼ teaspoon Sriracha, a big pinch of salt and a few grinds of black pepper. Even though the miso and ponzu are salty, you need more salt to counterbalance the syrup and enliven the jam. Taste and add more Sriracha, salt and/or pepper, if you’d like. (You can pack the jam airtight and keep it in the refrigerator for up to 3 days.)
The simplest way to serve this dish is to let everyone split their potatoes and slather on some of the miso jam. Alternatively, line the baking sheet that the potatoes roasted on with clean foil and lightly butter or oil it. Cut the potatoes into chunks and place them flesh side up on the sheet. Press them down with a fork — don’t overdo it, you just want to create a few grooves — and spread some jam over each chunk. Return the potatoes to the oven for another 10 minutes.
Pass the rest of the maple-miso jam at the table, so that everyone can have a little more.
Storing: The potatoes are meant to be served as soon as they’re roasted. However, if you have leftovers, you can remove them from their skins, mash them with some miso jam and reheat them in a 350-degree-F oven.