Mix in half of the flour mixture, followed by the buttermilk and then
the rest of the flour mixture.
Add in
the rest of the flour mixture and beat on low speed until almost combined, then add in the rest of the buttermilk and beat on low until all mixed in.
Add
the rest of the flour mixture and mix until just combined.
Spread
the rest of the flour mixture on top of the blueberries.
Once almost combined, add in the pumpkin, chocolate chips and
the rest of the flour mixture and stir until almost combined.
Beat in
the rest of the flour mixture until everything is well combined.
Add
the rest of the flour mixture, beating as you go, and then finally the sour cream.
Stir in half the buttermilk, then half the flour mixture, the rest of the buttermilk, and then
the rest of the flour mixture.