While the oven is preheating, place the water in a medium sauce pan over high heat. When the water boils, stir in the brown rice.

Reduce heat to medium-low and simmer, partially covered, for about 40 to 45 minutes.

Do not boil away all of the liquid and do not stir the rice.

When a very small amount of liquid remains, remove the pan from the burner and let it stand, covered, for 5 minutes before serving.

Cut the white part of the green onion away from the green tops (leave the white part in a single large piece). Cross cut the green tops into about 1 inch lengths.

Place 1 teaspoon of the sesame oil in the pan and add the white part and half of the green tops of the green onion. Toss and roast for about 5 minutes in the oven.

Add the mushrooms, toss well, and return the pan to the oven for about 15 minutes. Toss the vegetables about every 5 minutes.

After 15 minutes add the edamame, toss well, and return to the oven, continuing to toss the vegetables every 5 minutes.

While the vegetables are roasting, place the remaining 3 teaspoons of oil, vinegar, lime juice, mustard, red pepper flakes, soy sauce, and honey in a large mixing bowl. Whisk until blended.

About 5 minutes after adding the edamame to the pan, add the tuna to the pan in the oven and toss well. Roast for about 7 minutes, toss well, and then add the tuna and vegetables to the sauce in the mixing bowl.

Toss well and serve over the brown rice.