Mince the garlic, parsley, and dill finely.
In a small bowl, whisk together half of the olive oil, the lemon juice, garlic, parsley, and dill to create the sauce.
Season the tuna steak, asparagus, and cherry tomatoes with sea salt and black pepper.
Heat a skillet over medium-high heat with a drizzle of the remaining olive oil.
Sauté the asparagus and cherry tomatoes for 4-5 minutes until the asparagus is tender-crisp and tomatoes begin to burst.
Remove the vegetables from the pan and set aside.
In the same pan, sear the tuna steak for approximately 2 minutes per side for a medium-rare finish.
Slice the tuna against the grain and serve alongside the vegetables, drizzling the vibrant lemon-herb sauce over the top.