Heat oven to 375°F.
Heat olive oil in a large (14-inch) skillet over medium-high heat. Add 1 pound ground turkey and cook, breaking up with a spoon, for 3-4 minutes until mostly browned.
Add diced bell pepper and 2 sliced scallions and cook for 3-4 minutes until softened. Stir in 2 cups cauliflower rice, a 5-ounce bag spinach, 2 cups marinara sauce, 1 teaspoon garlic powder, 1 teaspoon onion powder,1/2 teaspoon kosher salt, and 1/2 teaspoon black pepper. Cook, stirring, until veggies are tender, spinach is wilted.
Reduce heat to low. Stir in 4 ounces cream cheese until melted and well combined. Spoon turkey mixture into a 3 quart (medium) casserole dish (not a 9x13).
Combine 1 cup shredded mozzarella cheese, 1/2 cup grated parmesan, and 2 tablespoons everything bagel spice in a small bowl. Sprinkle over the top of the casserole.
Bake for 18-20 minutes, or until cheese is melted and bubbly. Let cool 5-10 minutes before serving.