Tart and crispy fresh tuna salad

Ingredients:

• 2 large fresh tuna steaks (about 700 g)
• 2 lemons, thinly sliced, plus juice and zest of half a lemon
• 1 cup nonfat Greek yogurt
• 0.5 cups red grapes, halved
• 1/4 cup toasted chopped walnuts

Preparation:

1. Preheat oven to 175°C.
2. Place a large sheet of parchment paper on a baking sheet. Arrange the lemon slices on the parchment, overlapping them slightly, covering an area slightly larger than the steaks. Season the fish generously on both sides and place it directly on the lemon slices.
3. Sprinkle the zest evenly over the tuna. Bring the two long sides of the parchment paper to the center and fold them over the tuna; fold the ends of the parchment paper over and tuck them under the tuna like an envelope.
4. Bake in the oven until cooked through, about 18-20 minutes; the tuna should flake easily with a fork and no longer be pink in the center.
5. Open the parchment wrapper and let the tuna cool enough to handle, then flake it with a fork.
6. Transfer to a serving bowl along with any juices. Add the yogurt, grapes, and walnuts and toss to combine. Season with salt, pepper, and a squeeze of freshly squeezed lemon juice to taste. Serve immediately or refrigerate until ready to serve.
7. Serve this healthy salad on oiled lettuce leaves on a slice of toasted whole grain bread with fresh melon slices, or eat straight from the refrigerator.