Preheat the oven to 425°F (220°C). Line a baking sheet with parchment paper or a silicone baking mat.
Trim the cauliflower and cut half into thick steak-like slices. Break the remaining half into florets.
Place the cauliflower florets and the peeled garlic cloves into a saucepan. Cover with water and bring to a boil.
Reduce the heat and simmer for about 15 minutes, or until the cauliflower is very tender.
Drain thoroughly and transfer the cauliflower and cooked garlic to a food processor.
Add the butter, cream cheese, water, salt, and pepper. Blend until smooth and creamy. Set aside and keep warm.
In a small bowl, whisk together the sriracha, honey, soy sauce, and minced garlic until well combined.
Arrange the cauliflower steaks on the prepared baking sheet and brush both sides generously with the honey sriracha glaze.
Roast for 15 minutes.
Carefully flip the steaks, brush with additional glaze, and continue roasting for another 5 to 10 minutes until tender and caramelized around the edges.
Meanwhile, heat the olive oil in a small skillet over medium heat.
Add the spinach and cook for 2 to 3 minutes until just wilted.
Spread the mashed cauliflower onto serving plates.
Top with the sautéed spinach.
Place a roasted cauliflower steak on each serving.
Sprinkle with fresh pomegranate seeds and serve immediately.