Healthier choice recipe: Sweet potato with miso 'butter'

SINGAPORE - You can have too much of a good thing: I spotted yet more sweet potatoes in my organic vegetable box, which is delivered to me weekly by a supplier.

I love sweet potatoes, but how many dishes can I make from this root vegetable, although it is healthy?

Already, at times when I have sweet potatoes, I add them to curries like the Vietnamese do.

I also use it in soups, such as the spicy nonya soup titek, in which the stock is flavoured with belacan, onion and chilli, then garnished with a scattering of basil leaves.

And yes, I may also steam it plain like the Japanese do, though that seems abstemious.

That was before I discovered this lovely yet simple recipe: Roasted sweet potato topped with miso butter.

It makes for a delicious mouthful - creamy sweet potato ameliorated with a salty-sweet butter, which is made from mixing butter and white miso.

I wanted to eat it again and again.

However, given that I try to eat as little saturated fat as possible, I had to rethink the recipe.

Could I substitute the butter with monounsaturated olive oil?

I tried and it worked.

This emulsified paste is rich with the flavour of miso and sweet with mirin, which is a sweet rice wine. (You could, at a pinch, use rice wine with a little sugar added to it.)

It went perfectly with the roasted sweet potato and it has become one of my favourite recipes.

Not all potatoes are made equal.

Simply put, the sweet potato is king.

In fact, some nutritionists would describe it as a superfood.

According to the Centre for Science in the Public Interest based in the United States, the sweet potato is the most nutritious vegetable of all.

The centre is a non-profit watchdog and consumer advocacy group that advocates safer and healthier foods to the public.

According to its nutritionists, the sweet potato, with a score of 184, outscored the next highest vegetable by more than 100 points.

The higher the score, the more nutritious the food.

Points were given for its dietary fibre, naturally occurring sugars and complex carbohydrates, protein, vitamins A and C, iron and calcium.

Points were deducted for its fat content (especially saturated fat), sodium, cholesterol, added refined sugars and caffeine.

Overall, the sweet potato is rich in complex carbohydrates, dietary fibre and beta-carotene, with moderate contents of other micronutrients, including vitamins B5 and B6, manganese and potassium.

Indeed, a small sweet potato provides almost half the daily recommended amount of potassium and vitamin C.

Sweet potatoes would even tie for first place with carrots when it comes to the amount of beta-carotene they contain.

This makes them ideal for fighting diseases like cancer and heart problems, as well as diseases related to inflammation, such as asthma and rheumatoid arthritis.

Furthermore, the sweet potato has a low glycaemic index (GI), which indicates the impact a food has on a person's blood sugar levels.

A high GI means blood sugar levels can spike after taking the particular food. Diabetics and others who monitor their blood sugar levels try to avoid high-GI foods.

Despite its rich mouth feel, sweet potatoes have a GI of only 17, compared with 29 for a white potato.

Indeed, some nutritionists even believe that the single most important dietary change for most people would be to replace fatty foods with foods rich in complex carbohydrates, such as sweet potatoes.

Never again would I complain about getting too many sweet potatoes in my vegetable box.


Sweet potato with miso 'butter' (Serves 5-6)


4-5 evenly sized sweet potatoes, about 500g in all
1-2 tbs white miso paste
4 tbs olive oil
2 tbs mirin (Japanese sweet rice wine)
2 stalks fresh spring onion, chopped


1. Scrub the potatoes and prick holes with a fork all over them.

2. Roast uncovered, skin on, at 180 deg C for 45 minutes.

3. While the sweet potatoes are roasting, mix the ingredients for the "butter" together: miso paste, thinned out with olive oil and mirin and mixed well to obtain a soft butter-like consistency.

4. Adjust to taste with a bit of sugar, if desired.

5. The sweet potatoes are ready when the skin gives way a little when gently pressed.

6. Remove from the oven and slice them open lengthwise.

7. Place a dollop of miso butter on each sweet potato and serve immediately.

8. Garnish with chopped spring onions. Enjoy as part of a meal or as a snack.

Sylvia Tan is a freelance writer and cookbook author. Her previous recipes for Eat To Live can be found in two cookbooks, Eat To Live and Taste.

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