Preheat oven to 325 degrees F (165 degrees C). Line a 9x13-inch baking sheet with aluminum foil; coat with cooking spray.
Combine honey and peanut butter in a microwave-safe bowl; microwave on high until melted, about 20 seconds. Stir well.
Place the rolled oats in a large bowl. Drizzle honey-peanut butter mixture over oats; toss to coat. Mix in sunflower seeds, chocolate chips, coconut, brown sugar, vanilla extract, and cinnamon until evenly combined. Spread mixture onto the prepared baking sheet.
Bake in the preheated oven until lightly browned, about 22 minutes. Let cool for 20 minutes.