THAI MUNG BEAN CUSTARD RECIP (KHANOM MOR GAENG)
Discover the unique sweet and savoury balance of Khanom Mor Gaeng, a traditional Thai baked custard. This recipe uses rich eggs, creamy coconut milk, and sweet palm sugar, thickened with hearty mung beans. It is famously topped with crispy fried shallots, creating an irresistible aroma and flavour combination that is truly authentic to Thai cuisine.
Ingredients (for 6-8 servings):
- 200g split yellow mung beans (soaked for at least 3 hours)
- Large free-range eggs
- 250g palm sugar (finely chopped)
- 400ml full-fat coconut milk
- 3-4 pandan leaves, tied into a knot
- 1/2 tsp salt
- 10-12 shallots, thinly sliced
- 4 tbsp vegetable oil (for frying shallots)
Method:
- Prepare the Mung Beans: Drain the soaked mung beans and rinse thoroughly. Steam on high heat for about 20-25 minutes until they are soft and can be easily mashed between your fingers.
- Mash the Beans: Whilst still warm, transfer the steamed beans to a bowl and mash them well with a fork or potato masher until relatively smooth (some texture is fine). Alternatively, you can blend them lightly in a food processor.
- Fry the Shallots: Heat the vegetable oil in a small frying pan over medium heat. Add the sliced shallots and fry slowly, stirring frequently, until they turn golden brown and crispy. Be careful not to burn them. Remove the shallots with a slotted spoon and drain on kitchen paper. Important: Reserve the fragrant shallot oil in the pan; let it cool slightly.
- Make the Custard Base: In a large mixing bowl, crack the eggs and add the palm sugar, salt, and the knotted pandan leaves. Using your clean hand (or a whisk), scrunch and squeeze the pandan leaves into the eggs and sugar. Continue until the sugar is completely dissolved. This step infuses the custard with the sweet aroma of pandan.
- Combine: Remove and discard the pandan leaves. Pour in the coconut milk and whisk well to combine. Strain this mixture through a fine-mesh sieve into another bowl to ensure a smooth custard.
- Mix Everything: Add the mashed mung beans and about 2 tablespoons of the reserved shallot oil into the strained custard mixture. Whisk well so everything is evenly incorporated.
- Pre-cook (Optional but Recommended): Pour the mixture into a large wok or saucepan. Cook over medium-low heat, stirring constantly for about 5-8 minutes until the mixture thickens slightly (like heavy cream). This helps prevent the beans from sinking to the bottom during baking.
- Bake: Preheat your oven to 180°C (Fan 160°C). Pour the thickened mixture into a greased square or rectangular baking tray (approx. 8×8 inches). Bake for 35-45 minutes, or until the custard is set and the top is golden brown.
- Serve: Remove from the oven and let it cool completely in the tray. Before serving, sprinkle the crispy fried shallots generously over the top. Slice into squares and serve.
Note:
- The Shallot Oil: Do not skip adding the reserved oil from frying the shallots into the custard mixture (Step 6). This is the secret to the authentic aroma of Khanom Mor Gaeng.
- Eggs: This recipe uses large chicken eggs which are easier to find in the UK. The result is a lighter, delicate custard. (Traditionally, duck eggs are used for a denser texture and deeper orange colour).
- Texture: For a super smooth texture, you can blend the steamed beans with the coconut milk before mixing with the egg mixture. However, traditionally, a little bit of texture from the mashed beans is desired.
- Storage: Keep leftover custard covered in the refrigerator for up to 3 days. It is delicious served either at room temperature or slightly chilled.
