Preheat oven to 400F; prepare your 12-cup muffin pan by greasing it with cooking spray.
In an electric mixer bowl, add both flours, baking powder, salt, cinnamon, and nutmeg. Turn mixer on until the dry ingredients are well combined.
With the mixer on low, add the cubed butter and continue mixing until it resembles coarse crumbs. Add the milk and mix until a dough forms into a ball that comes away from the side of the ball. Turn dough onto floured counter and let rest for 5 minutes.
While the dough rests, melt the butter for the filling. Combine the brown sugar and the spices.
Cut the dough in 2 equal parts and let rest for 10 minutes. The filling recipe above is enough for both halves.
Once the dough has rested, roll the first half into a rectangle that is approximately 8″x 12″. Brush dough with melted butter, getting as close as possible to the edges. Sprinkle with half of the brown sugar/spice mixture.
Beginning with the long edge closest to you, snugly roll the dough together. Once you’ve finished, pinch the raw edges together to seal the roll. Cut the long roll into 6 equal pieces, each one approximately 2″ in length. Place in greased muffin tin.
Repeat the previous two steps with the remaining dough.
Peel the outermost layer of each roll out and curl the edges under, so they begin to look like roses. You don’t have to do this step, but it does add to the overall appearance once they’ve been baked.
Bake in 400F oven for 25 minutes. The buns will be a lovely golden brown!