Sprinkle the grouper steaks on both sides with 1/4 tsp of the salt and 1/8 tsp of the pepper. In a large, nonstick frying pan, heat 1 1/2 tsp of the olive oil over medium high heat. Add the fish to the pan and sear on both sides until lightly browned, about 2 minutes per side. Transfer to a plate and keep warm.
Reduce the heat to medium and add the remaining 1 T. olive oil to the pan. Add the onion and saute until soft and lightly golden, about 6 minutes. Add garlic and saute 1 minute more.
Add the tomatoes, olives, capers, and jalapeno and simmer for 10 minutes to allow the flavors to blend. Stir in the remaining 1/4 teaspoons salt and 1/8 teaspoons pepper.
Return the fish to the pan, cover, and simmer until the fish is opaque throughout when tested with the tip of a knife, 6-8 minutes.
Transfer the grouper steaks to warmed individual plates/ Stir the lime juice into the vegetables and pan juices and spoon some sauce over each steak. Serve immediately.