My Cantonese Mom’s Tip for Buying the Best Sweet Potatoes

Every Sunday, from late 1990 to the early 2000s, my mother and I would navigate the bustling streets of New York City’s Chinatown to shop for groceries. We’d roam the fruit and vegetable stalls, where the scent of fresh lychees mingled with the occasional whiff of heavenly durian.

During these shopping excursions, my mother taught me how to pick the best fruits and vegetables. Heavy oranges meant they were full of juice. If grapes were plump, they were good to go. Anything with bruises was a red flag. As for our favorite sweet potatoes (the Japanese kind—satsumaimo, or さつまいも), Mom had a clever trick up her sleeve, too. 

“Always pick the slender and long ones,” she told me in Cantonese. 

“Not the heaviest or biggest ones?” I asked her. 

Why You Should Choose Long, Slender Sweet Potatoes

Mom shook her head and explained that when cooked, longer and more slender sweet potatoes will always taste better than their bigger, heftier counterparts. In the oven, long, slender sweet potatoes cook more evenly. The skin caramelizes thoroughly, and the even cooking enhances the root vegetable’s natural sweetness.

The bigger and fatter the potato, the longer it takes to roast thoroughly, and you’re more likely to end up with a hard, uncooked middle. Large and round sweet potatoes also contain more water, which can dilute the potato’s sweetness. 

To drive her point home, Mom roasted several long, slender sweet potatoes alongside one large, round contender. The verdict was clear after an hour in the oven and extensive taste testing. The slender ones were caramelized to perfection, thoroughly tender, and oh-so-sweet, whereas the fat, round one was still slightly undone in the middle. Maybe it was a placebo effect, or my young tastebuds really were that discerning. The fatter potato just didn’t taste as sweet. 

I’ve used my mother’s trick for decades, applying it to other varieties of sweet potatoes, making every roast sweeter and more satisfying. But if I can be honest for a second, I have to say that Japanese sweet potatoes are still my favorite, with a flavor that other varieties can’t quite match. Out of the oven, they’re nutty and buttery, like big, sweet chestnuts. 

Perhaps I’m biased. Each roast takes me back to my childhood and those quiet moments with my mother. She didn’t nurture me with gentle, flowery words. Cantonese is a direct and unembellished language; my mother was no exception. But through food and our impromptu kitchen experiments, she brought sweetness to my young life with the sweetest sweet potatoes. For that, I’ll always be grateful.