Place chickpeas in a large bowl, then cover completely with water. Add Kosher salt, then let sit.
Drain the chickpeas, rinse under cool water, then place in a large pot and cover completely with water. Add baking soda. Cook at a simmer until the chickpeas are very tender. Skim off any residue that accumulates at the top.
Immediately place them in a food processor with tahini, reserved cooking liquid, the juice of lemon, Kosher salt, and ice cubes. Blend until very smooth. Taste, adjust seasoning.
Heat olive oil. When hot, add diced mushroom caps then cook, stirring occasionally, until browned. Add ground lamb, then season with za’atar, Kosher salt, ground cinnamon,ground allspice, and white pepper. Cook until the lamb is fully cooked through.
Top the hummus with the ground lamb and mushroom mixture, piled high in the center. Drizzle with a high quality extra virgin olive oil, then garnish with chopped parsley, ground cumin, a little paprika, and additional pine nuts. Enjoy warm with pita!