1. In a small bowl, combine the soy sauce, water, mirin, garlic, ginger, sesame seeds, and cornstarch. Stir until the cornstarch is dissolved. Divide into 2 halves.

2. Remove the scales and skin from the salmon, if needed. Cut it into 2 equal pieces and place them in a ziplock bag. Add Half 1 of the marinade to the bag and let the fish marinate for about 15 minutes. Save the second half of the marinade for the green beans later.

3. While the fish marinates, preheat the oven to 350F. Bring a pot of water to a boil to cook the frozen green beans in (no need to thaw). 

4. Boil the green beans for about 3 minutes, til crisp tender. Drain. Set aside.

5. Once the fish finishes marinating, remove it from the marinade. Bake the salmon in the oven for about 10 minutes, til nearly done. While it bakes, simmer the used marinade half 1 in a pot on the stove, boiling it to reduce it to a glaze.

6. Heat a skillet. Add the green beans along with the remaining unused marinade half 2. Saute the green beans in the marinade until it thickens to a shiny glaze and coats the green beans (about 3 minutes). 

7. Once the fish is nearly cooked, put the reduced glaze 1 on top and place fish under grill for 2-3 minutes. 

8. Serve hot.