Preheat a well-oiled grill to medium-high heat. Wash and dry produce.

Halve, core, and thinly slice green pepper into strips. Halve, peel, and thinly slice onion. Halve lime crosswise; thinly slice one half into rounds and quarter remaining half. (For 4 servings, thinly slice one lime; quarter remaining.)

OVEN ALTERNATIVE: Adjust rack to top position (top and middle positions for 4) and preheat oven to 425 degrees.

In a small bowl, combine Tex-Mex paste and 1 TBSP sugar (2 TBSP for 4 servings) until sugar has dissolved.

Pat cobia* dry with paper towels; season generously all over with half the Mexican Spice Blend, salt, and pepper. Evenly coat both sides with Tex-Mex rub.

Cut two 18-inch-long pieces of foil (four pieces for 4 servings) and arrange on a clean work surface with long side facing you.

Evenly divide green pepper and onion lengthwise in the center of foil. Top each with a large drizzle of oil and season with remaining Mexican Spice Blend, salt, and pepper; toss to coat.

Top veggies with cobia. Arrange lime rounds on top of fish.

Fold foil over fish and veggies, then cinch into packets. TIP: Tightly sealing the packets will ensure that the fish steams properly.

Place grill packets on grill, cinched sides up.

Close lid and grill until veggies are tender and fish is cooked through, 8-10 minutes. Transfer to a plate. TIP: When checking for doneness, carefully open the packets with tongs—there will be steam!

OVEN ALTERNATIVE: Place packets, cinched sides up, on a baking sheet (two baking sheets for 4 servings). Roast on top rack (top and middle racks for 4), 18-20 minutes.

While packets cook, in a medium bowl, combine cabbage, mayonnaise, juice from two lime wedges (four wedges for 4 servings), salt, and pepper. Toss to evenly coat.

Wrap tortillas in foil. Grill until warm and pliable, 30-60 seconds per side.

MICROWAVE ALTERNATIVE: Wrap tortillas in damp paper towels and microwave for 30 seconds.

Carefully open grill packets. Discard lime rounds. Using a fork, break up cobia into bite-size pieces (it’s OK if the fish and veggies mix together!).

Divide tortillas between plates. Fill with cobia and fajita veggies; top with slaw. Drizzle with red pepper crema and serve with a squeeze of lime juice and any remaining lime wedges on the side.