Preheat your oven to 350°F (175°C) and line a 9×5-inch loaf pan with parchment paper, leaving some overhang for easy removal. If making your own oat flour, blend 3 cups of rolled oats in a food processor or high-powered blender until you achieve a fine, powder-like consistency. Measure out 2½ cups for the recipe.
In a large bowl, whisk together the oat flour, baking soda, baking powder, salt, cinnamon, nutmeg, cloves, and ginger until well combined. The mixture should look uniform with spices evenly distributed.
In a separate medium bowl, whisk the eggs until lightly beaten. Add the pumpkin puree, maple syrup or honey, melted coconut oil, milk, and vanilla extract. Mix until smooth and well incorporated.
Pour the wet ingredients into the bowl with the dry ingredients. Using a spatula or wooden spoon, fold the mixtures together until just combined. Be careful not to overmix – stop when you no longer see dry flour.
If using, gently fold in your chosen mix-ins like chopped walnuts, chocolate chips, or dried cranberries. Distribute them evenly throughout the batter with just a few strokes.
Pour the batter into your prepared loaf pan and smooth the top with a spatula. Bake in the preheated oven for 50-55 minutes, or until a toothpick inserted into the center comes out clean with just a few moist crumbs.
Allow the bread to cool in the pan for 10 minutes, then use the parchment paper overhang to lift it out onto a wire rack to cool completely before slicing.