1. For salsa, cut the mango around the seed into two pieces. Using a knife make ½-inch slices through the mango, but not all the way through the skin side. Turn and cut one in the middle.
2. Using a spoon scoop the pulp out. Now, cut them into small dice size pieces.
3. Wash cilantro in cold water, pop off the leaves and leave the stem behind. Chop cilantro leaves, and keep it aside.
4. For blackened seasoning, in a small bowl mix all the dry ingredients together.
5. On a tray, place the steak, sprinkle seasoning on all the sides. Rub it well. Leave aside to marinate until ready to cook.
6. For salsa, in a bowl combine mango, orange, and cilantro.
7. Put lime juice, and sprinkle salt on top. Toss it well and place it in refrigerator for an hour. You may also prepare the salsa a day ahead.
8. For tuna steak, place a skillet over heat, and pour olive oil in it. Add tuna steak to the skillet; allow it to brown, for about 2 minutes. Flip the tuna steak, and turn off the heat.
9. Stir in red wine and butter. Turn around the skillet and then place it on a tray to rest for 10 minutes.
10. Cook it again for another 3-4 minutes before you serve.
11. On a serving tray, spoon salsa, place tuna steak on top, garnish with cilantro and serve it with wine.
Your ripe mangoes should be firm, and should have a banana like feel when you touch.