Step 1

Light a grill. In a medium bowl, mash the avocados, sour cream, jalapeño, red onion, cilantro and 3 tablespoons of the lime juice. Season the guacamole with salt and pepper and press a piece of plastic wrap directly onto the surface of the guacamole.

Step 2

In a large bowl, toss the cabbage with the 2 tablespoons of vegetable oil and the remaining 2 tablespoons of lime juice. Season with salt and pepper.

Step 3

Brush the fish with oil and season with salt and pepper. Grill over moderately high heat until lightly charred and cooked through, about 10 minutes. Transfer the fish to a platter and pull off the skin.

Step 4

To assemble each taco, spread a dollop of guacamole on a tortilla. Top with a piece of fish, a few tomato slices and a large spoonful of the cabbage slaw. Serve with the hot sauce and lime wedges.