Cookwith - Filet Mignon Award-Worthy Tuna Steak with Lemon-Rosemary Butter

Ingredients

• 4 (6 oz) sushi-grade tuna steaks
• 2 tbsp olive oil
• 1 tsp kosher salt
• 1/2 tsp freshly ground black pepper
• 1 lemon, zest and juice separated
• 2 tbsp fresh rosemary, finely chopped
• 4 tbsp unsalted butter, softened
• 1 tbsp capers, rinsed and chopped
• 1/2 small shallot, finely minced
• 1/4 cup fresh flat-leaf parsley, chopped
• 1/2 cup cherry tomatoes, halved
• 2 cups baby arugula
• 1 tbsp extra virgin olive oil (for salad)
• Flaky sea salt, to finish