For the jumbles: In a large bowl, beat the butter and sugars together until fluffy and smooth.
Add in the vanilla, cinnamon, nutmeg, baking soda and salt. Beat in the egg, then slowly beat in the oats.
Add the flours in alternately with the pumpkin puree. Chill the dough for at least an hour.
Preheat the oven to 400 degrees. Line a baking sheet with parchment paper.
Using a large cookie scoop (mine is about 1/4 cup) or large spoon, drop balls of dough onto the cookie sheet (9-10 at a time).
Bake for 14 minutes, until they’re set. Let cool for 10 minutes and then remove from pan. The cookies will be soft.
For the glaze: Melt the butter in a small sauce pan over medium heat and cook until it is golden brown and has little flecks in it, about 3-4 minutes (watch closely).
Immediately pour the butter over the powdered sugar and scrape the pan to get the brown bits. Stir together and add in the milk, one tablespoon at a time until a smooth glaze is formed. Use the glaze right away, since it will harden.