Prepare the salsa verde: In a medium bowl, combine chopped parsley, basil, minced garlic, and capers. Whisk in olive oil, lemon juice, and Dijon mustard until smooth. Taste and season with salt and pepper as needed. For a slightly smoother texture, pulse the mixture a few times in a food processor, but keep it fresh and vibrant. Set aside to allow the flavors to meld while you cook the tuna.

Prepare the tuna steaks: Pat the tuna steaks dry with paper towels. Brush both sides with olive oil and season evenly with salt, black pepper, and smoked paprika (if using). This will help create a beautiful sear on the grill while keeping the inside tender and flavorful.

Grill the tuna: Preheat your grill (or grill pan) to medium-high heat. Place the tuna steaks on the grill and cook for about 2–3 minutes per side for rare to medium-rare, depending on thickness. Tuna cooks quickly, so be careful not to overcook—it should still be pink in the center for optimal flavor and texture.

Rest the tuna: Remove the steaks from the grill and let them rest on a cutting board for 2–3 minutes. This helps the juices redistribute and keeps the tuna moist.

Serve with salsa verde: Spoon a generous amount of the fresh salsa verde over each tuna steak. For an extra touch, drizzle a little more olive oil and a squeeze of lemon on top. Serve immediately with your choice of side dishes like roasted vegetables, quinoa, or a fresh salad.