It is hard to dispute the origin of Sambal Belacan. Indonesia has over 500 types of Sambal from Sabang to Merauke. I would argue however that Sambal Belacan may originate from Indonesia. There is a clear difference between Sambal Belacan that is being served in Malaysia and Singapore than the Sambal Belacan that is served from Indonesia. For one thing, Sambal Belacan in Indonesia uses fermented prawn paste where Singapore or Malaysia’s Sambal Belacan simply uses normal prawn paste. As a result in terms of taste, pungency, smell, aroma, and intensity, the Indonesian Sambal Belacan usually is more intense. 

Another clear differentiators would be the number of ingredients included. For example, Sambal Belacan normally in Singapore would be following the following recipes: 

Ingredients:

• 10-15 fresh red chilies (adjust according to your spice tolerance)
• 3-5 bird’s eye chilies (optional, for extra heat)
• 1-2 tablespoons belacan (shrimp paste)
• 1 tablespoon sugar
• 2-3 tablespoons fresh lime juice (from calamansi or regular limes)
• 1 teaspoon salt
• 2-3 cloves garlic (optional)

Ingredients:

• 10-15 fresh red chilies (adjust according to your spice tolerance)
• 3-5 bird’s eye chilies (optional, for extra heat)
• 1-2 tablespoons terasi (Indonesian shrimp paste)
• 1 medium-sized tomato, chopped
• 2-3 cloves garlic
• 1-2 shallots, chopped
• 1 tablespoon sugar
• 2-3 tablespoons fresh lime juice (from key limes or regular limes)
• 1 teaspoon salt
• 2-3 tablespoons vegetable oil