Preheat the oven to 350 F/176 C. In a large bowl mix together the eggs, pumpkin, oil, and sugar. Use a sturdy whisk, wooden spoon, or mixer.
In a separate bowl whisk together the flour, salt, baking powder, cinnamon, and nutmeg. You may use a sifter too if you like.
Add the dry ingredients about a third at a time into the batter. Don't use a mixer at this point, only use a sturdy whisk or a wooden spoon. Scrape the sides of the bowl as needed.
Prepare a muffin pan with paper cups and spoon in the batter into each about two thirds full.
Optional: Make the crumble topping by mixing together the flour, sugar, butter, and cinnamon with a fork. Sprinkle that on top of the muffins, before baking. Use extra flour if you like your crumble to be drier.
Bake the muffins for 23 to 26 minutes until a toothpick comes out clean when inserted. Allow them to cool for a few minutes in the pan and then remove them and allow them to cool on a wire rack completely. Enjoy!