1. Blend all ingredients for spices until fine. Set it aside. Rinse blender with a little water (about ½ cup) and leave it for later.
2. Heat up oil and fry aromatics for a few seconds and add in blended spices. Fry until paste shrinks and oil splits (pecah minyak).
If it looks a bit dry, add in a little more oil
3. Add in gulai spice and chilli paste and fry until aromatic, roughly 3 minutes.
4. Add in beef, tamarind juice, potato and water from blender. Simmer until beef is no longer pink.
A lot of meat juices will come out from the beef, so only add water after the beef is no longer pink. From there, you can gauge how much water you need to add
5. Add in more water until it is just enough to cover the pot. Simmer on low heat with the lid on and stir occasionally. Cook until beef is tender (ours took about 40 minutes).
6. Once beef is tender and potatoes are soft, pour in coconut milk and season with salt and sugar. Bring it to a boil again and turn off heat. Serve with rice and condiments.
If you don't like it too rich, you can completely omit coconut milk out of the recipe. Through I suggest to use just a little bit to bring the flavours together