A hallmark dish of Asian cuisine.
1/2 cup sugar
1 tbsp water
1/2 cup soy sauce
2 cloves garlic, sliced
3 slices of ginger (the size of a quarter)
3/4 pound sushi-quality tuna, cut from the centre part of the loin
6 tbsp sesame seeds, both black and white if you can get them
1/4 cup peanut oil
Step 1: In a very small saucepan, bring the sugar and water to a boil over high heat, stirring occasionally. When the mixture starts to turn brown around the edges, remove it from the heat and let it turn to a dark honey colour. Note that once the sugar starts to caramelize it is very hot and will caramelize rapidly.
Step 2: Stand back and carefully pour in the soy sauce. The caramel will generate a bit of steam and may spatter, so hold your hand out of the way. Stir in the garlic and ginger as the caramel is cooling. Let them infuse at room temperature for at least 30 minutes. Strain out the ginger and garlic before serving.
Step 3: Wet the tuna with fresh cool water and roll in sesame seeds so that each surface is evenly coated. Heat the peanut oil in a skillet over medium-high heat. Season the fish lightly with salt, place in the skillet, and sear for about 1 minute or less on each side. The seeds should be toasted and light brown. The inside of the tuna should be quite rare. The heat should not be too high or the seeds will burn.
Step 4: Let the tuna cool and then slice it thinly with a very sharp knife. Serve with the caramel soy as dipping sauce.