To a large bowl, add pumpkin, eggs, and sourdough discard. Whisk until combined. Then add oil, maple syrup, vanilla, and sugars. Whisk until combined.
To a large bowl, add flour, almond flour, baking soda, baking powder, cinnamon, ginger, cardamom, and salt. Whisk to combine.
Make a well in the center of the dry ingredients and pour the wet mixture in. Stir with a spatula until just combined and no dry streaks remain. Set aside and cover loosely with a towel.
Meanwhile, preheat the oven to 400 degrees F. (We are leaving the batter sit on the counter during this time to let the wet ingredients absorb the dry, which helps the muffins rise higher.) While this is happening, make the streusel by whisking together all ingredients except butter. Then add the melted butter and stir to combine, gently squeezing with hand to know that it sticks into crumbles. Set aside.
When oven has preheated, grease muffin tin and place a muffin liner in every other muffin hole. Use a cookie scoop to fill each cup until just short of the lip. Divide an even amount of streusel over the top of each muffin.
Place muffin tin in the oven and turn it down to 375 degrees F. Bake for 21 to 22 muffins, until toothpick comes out with moist but not wet crumbs. Let cool on a wire rack.