Adjust rack to top position (top and middle positions for 4 servings) and preheat oven to 425 degrees
Bring a medium pot of salted water to a boil. Wash and dry produce.
Finely chop parsley. Peel and mince or grate garlic. Zest and quarter lemon (for 4, zest one lemon and quarter both).
In a small bowl, combine parsley, 3 tbsp olive oil (5 tbsp for 4), a pinch of garlic, a pinch of lemon zest, and lemon juice to taste. Season with salt and pepper; set aside.
Trim green beans if necessary; toss on one side of a baking sheet with a drizzle of olive oil, salt, and pepper.
Pat tilapia dry with paper towels; rub each fillet with olive oil. Season with Fry Seasoning, salt, and pepper. Place on empty side of sheet.
Roast on top rack until green beans are tender and tilapia is cooked through, 12-15 minutes. (For 4 servings, divide between 2 sheets; roast green beans on top rack and tilapia on middle rack.)
Meanwhile, once water is boiling, add couscous to pot. Cook until tender, 6-8 minutes. Drain thoroughly.
Melt half the garlic herb butter (all for 4 servings) in empty pot over medium heat. Return couscous to pot and stir until coated. Taste and season with salt and pepper.
Stir chopped almonds into bowl with gremolata. Add a small pinch of chili flakes if desired. Season with salt, pepper, and a squeeze of lemon juice to taste.
Divide couscous, green beans, and tilapia between plates. Spoon almond-parsley gremolata over tilapia. Scatter remaining almonds over green beans and top with a pinch of chili flakes if desired. Serve with any remaining lemon wedges on the side.