Place the tenderloins in a medium bowl. Add the balsamic vinegar, 1 tablespoon of the olive oil, 1 teaspoon of the salt, and ½ teaspoon of the pepper. Combine these ingredients to coat the pork well; cover and set aside. Combine the tomatoes, onion, garlic, and mint in a medium bowl. Whisk together the red wine vinegar and the remaining olive oil, salt, and pepper. Pour over the tomato mixture and toss well; cover and set aside. Place a large nonstick skillet or a grill pan coated with cooking spray over medium-high heat. When hot, add the tenderloins and cook about 3 minutes on each side. Turn heat down to medium and cook 6 to 8 minutes more per side, browning each evenly. Remove from skillet to a platter and let stand for 5 minutes. Slice each tenderloin into 8 pieces and serve with about 1/3 cup of the Tomato-Mint Salsa. Serve with sliced avocado and tortillas that have been warmed in the oven or on the stovetop.