Thinly slice the tuna steak (sashimi-style). Place the thin layers of tuna on a plate. Remove the rind and pith of 1/2 an orange, then slice and quarter. Remove the rind and pith of 1/2 a grapefruit, then slice and quarter. Lay the orange and grapefruit quarters on top of the tuna.
Juice the remaining orange half into a small bowl and whisk in the soy sauce and lemon juice. Drizzle the sauce over the tuna and citrus. Sprinkle the tuna with chopped mint and diced jalapenos.
In a small saute pan, heat the oil over high heat and quickly fry the rice noodles for 1 minute. Sprinkle them over the top and serve.
This recipe was created by a contestant during a cooking competition. It has not been tested for home use.