Preheat the oven to 350 degrees F. Mist an 8-inch square baking dish with cooking spray.
Bring a few inches of water to a boil in a pot with a large steamer basket in place. Put the sweet potatoes in the basket, cover and steam until tender, 20 to 25 minutes. Transfer the potatoes to a bowl and let cool slightly. Add the honey, egg, 1/2 teaspoon cinnamon, the nutmeg, ginger and 1/2 teaspoon salt; whip with an electric mixer until smooth. Spread the sweet potato mixture in the prepared baking dish.
Mix the brown sugar, pecans and the remaining 1/2 teaspoon cinnamon in a bowl; sprinkle over the potatoes. Bake until hot and beginning to brown around the edges, 40 to 45 minutes.