Pre-heat the oven to 350f degrees. Line an 8x8 or 9x9 baking dish with parchment paper.
Mix dry ingredients together (flours and baking soda). Separately, mix the wet ingredients together (puree, maple syrup, apple cider vinegar, oil, and milk).
Add the wet into the dry and mix well, then sprinkle in the seasonings.
Place mixture into the baking dish and spread evenly, bake for 5 minutes while you make the crumb topping.
To make the crumb topping:
Mix all ingredients with a whisk by hand or in a food processor until crumbs form.
Take the baking dish out of the oven and evenly pour the crumbs over top. Place back into the oven for 40 minutes.
When done baking, remove from the oven and let cool in the dish for a few minutes and then you can grab the corners of the parchment paper and transfer it to a drying rack.
For the Glaze:
While the crumb bars are cooling, heat all glaze ingredients in a small saucepan over low while stirring until you have a thick icing. Place the icing in a squeeze tube or anything you would use for icing so it can pour evenly.
Drizzle over the crumb bars and slice! (I didn't use all the icing, I stored for later use).
AIP Pumpkin Pie Crumb Bars https://foodbymars.com/aip-pumpkin-pie-crumb-bars/