Turn on the grill pan or a non-stick frying pan and heat it well. When the grill pan is hot, place the tuna steaks on it and cook them for about 2-3 minutes per side, depending on the thickness of the fish. Adjust the salt while cooking. Once the tuna steaks are cooked, place them in ice to stop the cooking process.

Separately, prepare the avocado cream. Cut the avocado in half, remove the stone and cut the flesh into small cubes with the tip of a knife. Remove the flesh from the peel with a spoon and blend in a food processor, adding the lemon, oil and salt.

To make the vinaigrette, take a bowl and mix together the unfiltered Balsamic Vinegar, mustard and salt. Gradually add the extra virgin olive oil, stirring continuously until the ingredients are completely blended and a smooth, velvety emulsion is obtained. If necessary, add more salt, pepper or vinegar according to your taste.

Serve the tuna steaks with the avocado sauce and the vinaigrette.