Preheat the oven to 350 degrees F
In a large bowl, whisk together the pumpkin puree, eggs, milk, oil, brown sugar, and vanilla until well combined.
Measure or weigh in the flour, baking soda, baking powder, salt and spices through a sieve. The whole wheat flour might not make it through the sieve, so just dump it in.
Use a spatula to gently stir the dry ingredients into the wet ingredients until almost combined. Add the seeds and cranberries (or whatever add-ins you're using) and stir until just combined. Do not overmix, or your muffins will be tough.
Grease or line a 12-muffin muffin tin and scoop the batter in.
Top with a few extra seeds if you'd like, and bake in preheated oven for 25-30 minutes.