Beat coconut oil, sugar, and molasses with an electric mixer over medium-high speed until light and fluffy, a minute or so. Beat in chia seed mixture, then pumpkin puree, followed by the dry ingredients to make a stiff batter. Spray 10 of 12 muffin cups with vegetable cooking spray. Use a large ice cream scoop to divide batter evenly among the 10 cups. (They will be full.) Generously sprinkle each cup of muffin batter with pumpkin seeds, pressing lightly on them to ensure they adhere. Bake until muffins are golden brown, about 30 minutes. Set on a wire rack to cool slightly, about 5 minutes. Remove muffins from tin and serve warm.