This is a cross between an Italian-Chicago beef sandwich, and Indonesian beef rendang. It's everything you want in a sandwich - spicy, sweet, and tangy.
Blend the chillies, shallots, garlic, ginger, lemongrass, lime leaves, and salt. This is your rendang base
Brown the beef in batches, seasoning with salt and pepper.
Add the paste to a pan with a splash of vegetable oil, star anise, cloves, cinnamon, bay leaves, and cardamom pods. Cook until slightly darkened, around 5 minutes.
Add coconut milk, water, sugar, tamarind paste, then add the beef back in. Stir, cover, and leave to cook on low for 2 hours, checking every half hour to ensure it's not stuck to the bottom. Add the coconut cream, then cook for a further 30 minutes.
For the sambal, toast the shrimp paste in a hot dry pan then add the vegetables. Lightly char before blending, either in a food processor or mortar and pestle.
Add everything back to the pan with lime juice, brown sugar, rice vinegar, and a pinch of salt. Cook until jammy and softened, around 10 minutes.
Build your subs - load up the beef onto the rolls, taking care to remove any whole spices. Top with the sambal, then finish with the pickles. Enjoy!