Begin by preheating your oven's broiler. Arrange the three tomato slices on a small, foil-lined baking sheet.
While the broiler heats, prepare the salads. In a small bowl, slice the cucumbers and toss them with the za’atar. Set aside.
In a separate bowl, combine the diced red onion, sliced bell pepper, parsley leaves, cumin, and lemon zest. Gently warm the 2 teaspoons of olive oil with the crushed garlic clove in a tiny saucepan for 30-60 seconds until fragrant, then discard the garlic. Drizzle this infused oil over the pepper and onion mixture and toss to combine.
Place the baking sheet with the tomatoes under the preheated broiler for about 5 minutes, or until softened and lightly charred at the edges.
As the tomatoes broil, crack the eggs into a medium bowl. Add the tahini paste, smoked paprika, salt, and pepper. Use an immersion blender to whip the mixture until smooth and pale.
Heat a nonstick skillet over medium-high heat. Pour in the egg mixture and let it set for a few seconds before using a rubber spatula to gently push the eggs from the edges toward the center. Continue this motion until soft, creamy curds form. Remove from heat just before they look fully cooked, as they will continue to set.
To assemble, place one warm broiled tomato slice in the bottom of each of three serving bowls. Top each tomato with 1 tablespoon of labneh. Divide the scrambled eggs evenly among the bowls, spooning them over the labneh. Sprinkle with sumac and serve immediately with the cucumber salad, pepper salad, and remaining labneh on the side, along with whole-grain crackers.