Every now and again, I get an urge to deep fry something for dinner. Whenever this is the case, I have a few solid recipes I turn to. One of those recipes are these amazing prawn and sweet potato fritters we Vietnamese call banh tom (which translates to prawn cake). This little bad boy is basically prawn-flavoured sweet potato chips that is usually wrapped in fresh lettuce and dipped in a tangy fish sauce. I promise you, when you try it, you won’t want to keep it to yourself.
Banh tom was first seen in the city of Hanoi near a famous lake called Ho Tay. It was originally made with thick cuts of sweet potato, small school prawns and a light batter to combine it all together. My family’s recipe is a variation of the authentic version since we have tinkered it to our taste. The main difference is that we like to add minced dried shrimp to the batter, so the prawn flavour is more prevalent throughout the fritter. Using this method also gives the option of serving without the fresh prawn, which will reduce the cost considerably.
There are many ways to serve banh tom but by far the most popular way is to have it as a starter. The simplest method is to plate the fritters with some lettuce leaves and nuoc mam dipping sauce. I usually add a few herbs and pickles for a little variety but these are completely optional.
This dish has had a lot of success at dinner parties, especially with those tasting it for the first time. There is just something about sharing plates of food and eating with your hands that brings people together. Banh tom is always a winner at my house and I strongly suggest you try it out. You won’t be disappointed!
Prawn and Sweet Potato Fritters - Banh Tom
Type: Starter / Shared plate
Author: Scruff & Mum
- 30 gm of dried shrimp
- 1.5 cups of boiling water
- 350 gm of sweet potato, peeled, julienne and rinsed
- 1 small onion, sliced
- 12 -15 small / medium raw prawns (see Note 2 and 5)
- Vegetable oil for deep frying
- 1/3 of a cup of self raising flower
- 1/3 of a cup of glutinous rice flour
- 1/3 of a cup of rice flour
- 1/2 tsp of turmeric power
- 1/4 tsp of salt
- Freshly cracked pepper
- 1 cup of reserved water from soaking the dried shrimp (see Note 1)
- 1 head of butter lettuce
- Nuoc mam dipping sauce (Click the link to my nuoc mam recipe)
- 1 bunch of Thai basil (optional)
- 1 bunch of coriander (optional)
- Soak the dried shrimp in boiling water for 20 minutes.
- Remove the shrimp from the water and save the shrimp water. Pound the soaked shrimp in a mortar and pestle or blitz for 10 seconds in a blender. Remember to save the water! (See Note 1)
- In a large mixing bowl, combine the batter ingredients. There’s no need to sift the flour.
- Add the shrimp, sweet potato, and onions to the mixing bowl and stir through.
- Prepare the prawns (see Note 2).
- Fill a deep pan with 3-4 cm of vegetable oil. Using a cooking thermometer, bring the oil temperature to 175°C – 180°C (347°F – 356°F).
- Before frying, use a pair of tongs to stir the mixture. This will ensure each piece of sweet potato is evenly coated just before frying.
- With the tongs, place the fritter mixture on a spatula and flatten.
- Coat the prawn in the batter and place it on top of the fritter.
- Slide the fritter off the spatula into the oil. I recommend frying no more than 2-3 fritters at a time, so the oil temperature does not drop too low (see Note 3).
- Cook each fritter for 2 mins on each side, or until golden (see Note 4).
- Remove the fritter and drain of the oil on a cooling rack.
- If you have accidentally thrown out the shrimp water (I have done this on a few occasions), just use tap water.
- How much of the prawn you use is completely up to you. Most people will remove the heads and legs of the prawn. We use the whole prawn because it looks more striking, and we eat the whole thing too. We figure anyone who’s not comfortable with eating the heads or any other part can just pick it off. My only suggestion is to keep the shell on to maintain the crispiness.
- Do not overcrowd the pan with fritters. This is because the temperature of the oil will drop significantly and the fritters will absorb oil instead of developing that crunch.
- Increasing the cooking time will give you a better crunch on the fritter. Be careful though as sweet potato contains high amounts of sugar which can burn easily.
- To improve the crispiness of the fritter, try to buy smaller prawns. This is because smaller prawns contain less moisture than larger ones.