Prep your pan and oven: Heat the oven to 350°F (175°C). Line a 12-cup muffin tin with liners or grease well. This batter can stick, so don’t skip this step.
Blend or whisk the base: In a large bowl, whisk together 1 cup pumpkin puree, 1/2 cup almond butter, 2 large eggs, 1/3 cup maple syrup, and 1 teaspoon vanilla until smooth.
If you prefer ultra-smooth muffins, use a blender for this step.
Add dry ingredients: Stir in 1 1/2 cups rolled oats, 1 teaspoon baking soda, 1 1/2 to 2 teaspoons pumpkin pie spice, and 1/4 teaspoon salt. Mix until combined; the batter will be thick but scoopable. If using a blender, pulse oats into a coarse flour first for a softer crumb.
Fold in extras: Gently fold in 1/2 cup dark chocolate chips or 1/3 cup chopped nuts if you like.
Keep the add-ins modest so the muffins rise well.
Fill the cups: Divide batter evenly among the muffin cups, filling each about 3/4 full. Sprinkle with pumpkin seeds or a few oats if you want a pretty top.
Bake: Bake for 16–20 minutes, until the tops are set and a toothpick comes out with just a few moist crumbs. Avoid overbaking; they should feel springy.
Cool: Let muffins cool in the pan for 5 minutes, then transfer to a rack.
They firm up as they cool, so give them a little time before peeling off the liners.