1. Heat the oil over medium-high heat in a large nonstick skillet. Add fennel slices and 1/8 tsp. of the salt. Saute, stirring frequently, until the fennel has softened and browned a bit on the edges, about 5 minutes. Add the tomatoes and another 1/8 tsp. salt and mix well. Cook another 3 to 4 minutes, stirring often, until the tomatoes soften. Add garlic and cook another minute. Transfer the mixture to a plate and let cool to room temperature while you prepare the fish.
2. Preheat oven to 400 degrees F. Line a rimmed baking sheet with foil.
3. Fold the fish fillets in half lengthwise along the center seam by tucking the thin side of the fillet under the thicker side. This will allow the fillets to cook evenly. Place the folded fillets in the prepared pan, thin side down. Cover the pan tightly with foil, shiny side down. Cook the fish 13 to 15 minutes, or until opaque, and just beginning to flake with a fork.
4. Cut grapefruit in half widthwise (between the top and bottom ends). Use a grapefruit or a paring knife to cut sections from the membranes. Use a spoon to scoop and transfer sections to a bowl. Squeeze any juice from the shell into the bowl (you will have about 1 to 2 cups sections and juice). Add the cooled fennel mixture along with 1/4 tsp. of the pepper and gently mix together.
5. When the fish is done, uncover the pan and season the fillets with remaining 1/4 tsp. salt and 1/4 tsp. pepper. Transfer fillets to plates, spoon the compote across the tilapia, and serve.
Source: Hannaford fresh Magazine, January - February 2011