Preheat your oven to 375 F and line a square baking tin or a baking sheet with some parchment paper and cooking spray.
Peel pumpkin and cut into cubes. If using squash (kabocha or butternut work well) there's no need to peel. Toss the cubes with maple syrup and coconut oil and roast until tender, for about 35 minutes. If the mixture is getting dry, pour in some of the soaking liquid from the dates.
Once softened, remove the roasted pumpkin from the oven and add to the bowl of a food processor or blender.
Line a square 9x9-inches brownie pan with parchment paper and preheat the oven to 350 F.
Add all the ingredients apart from baking powder and toppings to the blender or food processor and blitz until you have a nice and smooth paste. Add some orange food color, if you want a more vibrant orange. You want a thick mixture, but if your squash or pumpkin is very starchy, add some more of the date soaking water to help with blending.
Stir in the baking powder and pour the batter into your baking pan. Spread it out evenly and top with chocolate chips and pepitas.
Bake for 25 minutes, then let cool down to room temperature and chill in the fridge for at least 2 hours, better overnight!