Ofe Nsala

Preparation

1. Make the Trinity Pepper Paste

   Step 1

   Working in batches if necessary, use a mortar and pestle to combine the Scotch bonnet peppers and crayfish. Pound to a coarse paste. Add the irú and pound further until incorporated to a smooth paste. Alternatively, do this step in a food processor and pulse to combine the ingredients until chopped.
   
   Do ahead: Trinity pepper paste can be stored in an airtight container refrigerated for up to 1 week or frozen for up to 1 month.

2. Make the Ofe Nsala

   Step 2

   Remove the brown skin on the yam by peeling off with a paring knife or a vegetable peeler. Slice the peeled yam into pieces and keep in a bowl of water to keep from oxidizing. Rinse off the yam pieces and place in a medium saucepan. Cover with water and bring to a boil over medium-high heat. Season with salt and reduce the heat to a simmer. Allow the yam to cook until completely softened, 10 to 12 minutes.

   Step 3

   While the yams are cooking, use a sharp knife or large kitchen shears to cut open along the length of the back of each prawn. Cut deep enough to expose and remove the vein running down the prawn.

   Step 4

   Drain off any remaining liquid from the yam and once cooled enough to handle, crush the yam into smaller pieces using your fingers or the back of a fork. Cover and set aside.

   Step 5

   Bring the stock up to a simmer in a large pot set over medium-high heat. Gently poach the cleaned prawns by dropping them into the simmering broth. Cook until the prawns turn pink and firm, 1 to 2 minutes. Move the prawns to a plate and set aside.

   Step 6

   Into the broth, stir in the pepper paste, dried catfish, and afang leaves. Allow to simmer until the liquid is reduced to about three-quarters of the original volume. Strain the stock through a fine-mesh sieve to remove and discard the solids.

   Step 7

   Using a blender, carefully purée 2 cups of the stock mixture with the crushed yam pieces until smooth. Return the mixture to the pot, along with the remaining stock. Using a wooden spoon, stir the soup while cooking over low heat. Stir in the poached shrimp and adjust the seasoning with more salt if necessary. Add any fresh greens, if using. Cook until warmed through and beginning to simmer, 4 to 5 minutes. Divide the soup and prawns among bowls and serve warm.