In a mixing bowl combine lime juice, soy sauce, sesame oil, ginger paste, honey, salt, garlic powder, and pepper.
In a shallow dish place the ahi tuna steaks and pour the marinade over. Cover and refrigerate for at least 30 minutes up to overnight.
When you are ready to cook the tuna, remove it from the fridge and pour the sesame seeds on a plate and coat the tuna steaks in the sesame seeds on both sides.
In a dutch oven over high heat, heat the coconut oil for 2-3 minutes until the pot is very hot. It should look like its smoking.
Sear the ahi tuna for 30-60 seconds on each side and set aside to rest while you prep the salad.
In a large mixing bowl combine the chopped romaine, cucumber, green onions, cilantro, red cabbage and toss with the ginger salad dressing.
Slice the tuna against the grain and top the salad with the ahi tuna and sliced avocado.