In a small bowl, combine the sumac and za'atar. Set aside. In a medium saucepan over medium, heat 1 tablespoon of the oil until shimmering. Add the couscous and cook, stirring constantly, until lightly browned, 3 to 4 minutes. Transfer to a paper towel–lined plate and set aside.

To the same pan, add 1 tablespoon of the remaining oil, the shallot and minced garlic. Set over medium heat and cook, stirring constantly, until the shallot has softened, about 1 minute. Return the couscous to the pan, then stir in ½ teaspoon salt. Pour in ½ cup of hot water and cook, stirring, until most of the water is absorbed, about 2 minutes. Repeat this 4 more times for a total of 2½ cups water, cooking until the couscous is tender, 10 to 15 minutes. Off heat, stir in the lemon juice, butter and scallions. Taste and season with salt, then cover and set aside.

In a 12-inch nonstick skillet over medium, heat the remaining 3 tablespoons oil and the smashed garlic. Cook, stirring and flipping the garlic, until golden, 1 to 2 minutes. Remove and discard the garlic, then reduce to medium-low. Crack an egg into each quadrant of the pan and use a silicone spatula to gently push the edges of the egg whites toward the yolks to keep the eggs separate. Cover and cook until the whites are set but the yolks are runny, about 1½ minutes. Remove the pan from the heat.

Serve the couscous in individual bowls, topped with a fried egg and a generous pinch of the sumac mixture.