Ingredients

1/2 teaspoon arrowroot
1/3 cup low-sodium vegetable broth
1 medium pink grapefruit
1 medium orange
1 tablespoon minced jalapeno pepper (wear gloves to prevent irritation)
1 tablespoon roasted peanut oil
Freshly ground pepper
1/4 teaspoon salt
1 pound trimmed yellowfin tuna fillet, cut into 4 pieces
1/2 teaspoon finely grated lemon zest
1/2 teaspoon finely grated lime zest
1 cup very thinly sliced fennel bulb
1 red onion, very thinly sliced
2 teaspoons chopped fennel tops

Directions

Dissolve the arrowroot with 2 teaspoons of the broth in a small bowl. Bring the remaining broth to a boil in a small saucepan. Stir in the arrowroot mixture and cook, stirring, until thickened, about 30 seconds. Remove from the heat and let cool slightly.

Using a sharp paring knife, slice away the top and bottom ends of the grapefruit. Place on a cutting board on end and slice the rind away, removing all traces of pith. Working over a large bowl to catch the juices, cut the grapefruit sections out from between the membranes, letting each one fall into the bowl as you cut it free. Discard any seeds. Repeat with the orange.

Add the jalapeno and the juice from the citrus sections to the thickened broth. Whisk in the oil and season with pepper.

Spray the grill rack with nonstick spray and prepare the grill, or spray a nonstick ridged grill pan with nonstick spray and set over medium-high heat.

Season the tuna with the salt and pepper. Grill the fish 5 inches from the heat, until opaque in the center, 2 to 3 minutes per side.

Meanwhile, warm the dressing. Add the grapefruit and orange sections and the lemon and lime zest; warm through (do not stir or the grapefruit will break apart). Divide and arrange the fennel on each of four plates and top with the onion. Arrange the citrus salad next to the fennel. Drizzle the plates with the dressing and sprinkle with the chopped fennel tops. Makes 4 servings.

Nutrition information per serving: 244 cal., 9 g total fat (2 g saturated fat), 43 mg chol., 273 mg sodium, 12 g carbo., 3 g dietary fiber, 28 g pro.