Blend onions, ginger, and garlic together to form a paste. Heat oil in pan on mid high
Throw in your bay leaf and cinnamon stick, fry for 20 seconds. Then add in the pastes, and cook until raw smells are gone, adding some water if you need to keep it from burning
Reduce water completely, then add in your whole spices (cardamom, cloves, , black pepper pods), and fry for a couple of mins until aromatic, do not burn.
Add in your tomatoes and ground spices (turmeric, red chili, garam masala, cumin, coriander). plus a splash of water if needed.
Reduce and fry the everything in the oil for a minute then add in more water and repeat the process a few times, until the tomato turns into a paste, and the oils are released from the curry.
Then add in your tamarind paste, and sugar. Mix well.
Add in your coconut milk and simmer on low heat for a couple of minutes to bring everything together.
Add a half cup of water to your curry. Stir in the crabs so all the sides are covered in the gravy.
Simmer the crabs for 10 mins until cooked through. They should all turn bright red. Throw in your fenugreek leaves and split green chilis in the middle, and chopped cilantro a minute before taking it off the heat.
Plate your crabs. Garnish with some fresh cilantro and serve with lime wedges on the side.