1. Preheat the oven to 350ºF (180ºC). Line a baking sheet with parchment paper.
2. Prick the eggplants a few times around them with a paring knife. Set the eggplants directly over a gas burner and roast, turning occasionally with tongs, until they are soft and wilted, 5 to 10 minutes. (The longer you leave them on the flame, the more “roasted” they will taste.) Place the eggplants on the prepared baking sheet and bake until they’re soft all the way through, 20 to 30 minutes.
3. Remove the eggplants from the oven and when cool enough to handle, split them open and scoop out as much as the pulp as possible, and set it in a mesh strainer or colander. Let drain for 20 minutes, stirring it a few times while it drains. Once it’s drained, mash the eggplant with a fork until it’s a chunky puree.
4. Heat the olive oil in a skillet over medium heat. Add the onions and season with a bit of salt. Cook until wilted and translucent, stirring constantly, about 5 minutes, then add the garlic and cook for 1 minute more.
5. Add the eggplant and cook for another 5 minutes, stirring occasionally, seasoning with salt and pepper. Remove from heat and cool completely. Add the saffron to the water and let it steep.
6. Stir in the labneh and scrape the spread into a wide serving bowl. Spoon the saffron threads and the liquid over the spread and sprinkle with chopped walnuts.