Preheat your oven to 350°F (175°C). Lightly grease a standard 9×5 inch loaf pan with cooking spray or butter. For even easier removal, you can line the bottom and sides with parchment paper, leaving a slight overhang.
In a large mixing bowl, combine the softened pumpkin spice ice cream and the pumpkin puree. Stir until mostly smooth. Gently fold in the self-rising flour using a spatula. Mix only until the white streaks of flour disappear; be careful not to overmix, as this can make the bread tough.
Pour the thick batter into your prepared loaf pan and smooth the top with a spoon. Place it in the center of the oven and bake for 40 to 50 minutes. The bread is done when a toothpick inserted into the center comes out clean or with just a few moist crumbs.
Allow the bread to cool in the pan for at least 10 to 15 minutes before transferring it to a wire rack. Slicing it while it is too hot may cause it to crumble. Serve warm or at room temperature.