Fish Wrapped in Banana Leaves with Chile Rajas and Crema

Preparation

1. Make rajas:

   Step 1

   Roast chiles on racks of gas burners over high heat, turning with tongs, until skins are blackened, 10 to 12 minutes. (Or broil chiles on a broiler pan about 5 inches from heat, turning occasionally, about 15 minutes.) Transfer to a large bowl and cover tightly with plastic wrap, then let stand 20 minutes.

   Step 2

   When cool enough to handle, peel chiles, discarding stems and seeds (do not rinse under running water as this washes away flavor), and cut lengthwise into 1/4-inch-thick strips.

   Step 3

   Cook onions with salt in oil in a 12-inch heavy skillet over moderate heat, stirring, until onions are tender but still have texture, about 10 minutes. Stir in chiles and cook, stirring, 1 minute, then season with salt.

2. Assemble fish packets:

   Step 4

   Preheat oven to 450°F.

   Step 5

   Unfold banana leaves. Cut off (and reserve) tough center rib that runs along bottom edge of each leaf with kitchen shears. Cut ribs into 12- to 14-inch strips for tying packets. Gently cut leaves into 8 (12-inch) squares, being careful not to split them.

   Step 6

   Slowly run a banana-leaf square across flame of a gas burner, just enough to "melt" outer coating on leaf (it will become quite shiny; if you have an electric stove, hold leaf slightly above burner on moderately high). Place a piece of fish in center of square and season with salt, then top with 1/2 cup rajas and 2 tablespoons crema. Fold 2 sides of banana leaf over fish to enclose it, then fold in opposite sides to form a packet. Tie packet with a strip of banana-leaf rib and transfer to a large baking sheet. Assemble 7 more packets in same manner.

   Step 7

   Bake fish packets in middle of oven 20 minutes, then transfer each to a large plate or shallow soup bowl. Cut ties of packets and open them (leaves are not edible). Drizzle fish with additional crema.

3. Step 8

   • Available at Latino and Asian markets.