Preheat oven to 400°F. Heat 2 tablespoons oil in a large oven-safe skillet over medium heat. Add ½ cup onion, the chopped garlic and ½ teaspoon crushed red pepper; cook, stirring often, until the onion softens, 2 to 3 minutes.
Add 16 ounces baby spinach in batches; cook, stirring frequently, until wilted, about 7 minutes. Continue cooking, stirring occasionally, until the liquid reduces slightly, about 1 minute.
Add ½ cup broth; bring to a boil over medium-high heat, scraping up browned bits from the pan. Remove from heat; stir in rinsed chickpeas, 2 cups rice, 2 ounces cream cheese, ¼ cup dill, 3 tablespoons lemon juice and ⅛ teaspoon nutmeg until combined. Sprinkle with crumbled feta and stir gently once or twice.
Cover and bake until bubbling around the edges, 20 to 22 minutes. Let rest for 5 minutes. Sprinkle with 1 teaspoon lemon zest. Garnish with additional dill, if desired.
