Cauliflower Tikka Masala

Name: Cauliflower Tikka Masala
Ingredients: 1/2 cup sour cream or plain Greek yogurt; 2 tablespoons vegetable oil; 1 tablespoon mild or hot curry powder; 1 1/2 teaspoons sweet paprika; Kosher salt; 1 head cauliflower, broken into florets (about 4 cups); 3 cloves garlic, roughly chopped; One 1/2-inch piece fresh ginger, roughly chopped; 1 small yellow onion, roughly chopped; 2 teaspoons garam masala; One 28-ounce can no-salt-added tomato puree; One 14-ounce can chickpeas, rinsed and drained; 1 cup frozen peas, thawed; 2 tablespoons unsalted butter; 3 tablespoons chopped fresh cilantro, plus more for garnish; 6 cups cooked brown rice, for serving; Lemon wedges, for serving