Heat the oven to 425 F / 220 C. Line a sheet pan (33 x 46 cm / 13 x 18 inch) with parchment.
In a large mixing bowl, toss the cauliflower florets and chickpeas with olive oil, cumin, smoked paprika, coriander, cinnamon, chili flakes, minced garlic, salt, and pepper until evenly coated.
Spread the mixture on the sheet pan in a single layer, giving pieces room to touch the pan directly. Use a second pan if it looks crowded.
Roast for 25 to 28 minutes, stirring once halfway, until the cauliflower is deeply browned at the edges and tender when pierced with a fork.
While the vegetables roast, whisk tahini, yogurt, lemon juice, minced garlic, and salt in a small bowl. Add water a tablespoon at a time until the sauce pours like heavy cream.
Reduce the oven to 400 F / 200 C. Drizzle half the tahini sauce over the roasted vegetables and return the pan to the oven.
Bake for 8 to 10 minutes, until the sauce is bubbling at the edges and set on top.
Remove from the oven and let it rest for 3 to 5 minutes.
Transfer to a platter or leave on the pan. Drizzle with the remaining sauce and scatter parsley, pomegranate seeds, and toasted almonds over the top. Serve warm.