Preheat the oven to 350ºF and line a 9x9 baking pan with parchment paper.
In a large mixing bowl, combine the tahini, pumpkin, coconut sugar, eggs, baking soda, salt, pumpkin pie spice, and stir well to create a smooth, runny batter. Pour the batter into the baking pan and sprinkle with chopped pecans.
Bake the bars for about 20 - 22 minutes, until the top is firm and lightly golden. Allow to cool completely before slicing and serving. Store leftovers in an airtight container in the fridge for up to 1 week.