See notes on roasting fresh pumpkin
Preheat your oven to 350° F.
Prepare the crumble topping: In a medium bowl, combine the flour and sugar. Add cinnamon. Mash the vegan butter into the other ingredients with a fork until the crumbs form. Do not over-mix (it should be crumbly not a dough). Store in the refrigerator until ready to use.
Line a muffin tin with paper liners.
In a medium-large mixing bowl, fully combine the flour, startch, sugar, baking soda, baking powder, salt, cinnamon and pecans.
In a separate bowl, combine the pumpkin, banana, vegan butter, sourdough starter, vanilla, plant milk, lemon juice and flax. Whisk combined.
Gently fold the wet ingredients into the dry ingredients until everything is just combined. Do not over mix. The batter should be thick and its okay if there are a few clumps.
Spoon the batter into the muffin tins to be about ¾s full. Top with crumble topping.
Bake for 30-35 minutes total. rotate the pan halfway through.
Allow cooling for about 45 minutes