Heat your oven to 425°F and line a baking sheet with parchment paper. Wash and dry the pumpkins, then trim off the stems. Stand each one on its flat base and cut it into quarters with a sharp knife.
Use a large spoon to scoop out the seeds and stringy pulp from every quarter. Don't throw the seeds away, because you can roast them as a snack. A clean cavity helps the pumpkin roast evenly.
Brush the cut sides lightly with olive oil and place the quarters cut-side down on the pan. Roast for 35 to 40 minutes. The pumpkin is ready when a fork slides in with no resistance.
Let the quarters cool for a few minutes until you can handle them. The skin should peel away easily, and you can just discard it. Keep the soft, caramelized flesh and set it aside.
Set your Dutch oven over medium heat and add the chopped bacon. Cook for 5 to 6 minutes, stirring now and then, until crispy. Move the bacon to a plate, and leave about 3 tablespoons of grease in the pot.
Add the chopped onion to the hot bacon grease and cook for 6 to 7 minutes until soft. Stir in the garlic, salt, pepper, cinnamon, nutmeg, and allspice. Cook for 30 to 60 seconds until the kitchen smells amazing.
Add the roasted pumpkin flesh and the broth to the pot. Bring everything to a boil, then lower the heat to a gentle simmer. Cover partially and cook for 15 minutes so the flavors can blend.
Blend the soup right in the pot with an immersion blender until it turns velvety. If you use a standing blender, fill it only halfway and work in batches. Hot soup expands, so vent the lid to let steam escape.
Stir in the coconut milk or cream and bring the soup back to a boil. Add the maple syrup, then taste and adjust the salt and pepper. Toast the pepitas in a dry skillet until golden, then ladle the soup into bowls and top with bacon and pepitas.