First, make the tuna marinade. Combine Scallion (1 cup), Garlic (1 clove), Fresh Ginger (1 ounce), Serrano Chili (1) and Fresh Cilantro (1/4 cup) in a food chopper or food processor, chop finely, then transfer to a medium bowl.
Add the rest of the ingredients, Lemon (2 tablespoon), Brown Sugar (1 tablespoon), Dried Thyme (3/4 teaspoon), Ground Cinnamon (1/2 teaspoon), Ground Allspice (1 1/2 teaspoon), Sea Salt (1 teaspoon), Extra-Virgin Olive Oil (2 tablespoon), Soy Sauce (2 tablespoon), Fresh Ginger (1 tablespoon) from the marinade; mix well.
Add thawed Fresh Tuna Steak (12 ounce) into the marinade, combine and coat well. Cover and marinate for 4 hours or overnight.
When ready to cook, add Quinoa (1/2 cup) and 1 cup of water in a small saucepan. Bring to a boil and simmer for 10-15 minutes until the quinoa is tender and fluffy. Set aside.
Heat up Extra-Virgin Olive Oil (2 tablespoon) in a 10-inch cast-iron skillet over medium-high heat. Add Sweet Onion (1 cup), Red Bell Pepper (1), Zucchini (1) and cook for 5 minutes or until the vegetables start getting tender.
Stir in tuna with the marinade and diced Pineapple (1 cup) into the skillet, stir a couple times and then add Soy Sauce (1 tablespoon) and Lemon Juice (2 tablespoon) Continue cooking for about 5 minutes or until the tuna is cooked through.
Remove from heat; add the quinoa into the skillet; combine well; garnish with chopped Scallion (to taste) and chopped Fresh Cilantro (to taste) before serving. Enjoy!