Dice onion and mince garlic cloves
Melt butter over medium heat in stockpot or sauce pot.
Add in diced onion with minced garlic.
Cook and stir until onions are soft and tender.
Mix together flour, black pepper, salt, Old Bay seasoning, cayenne pepper in a small bowl.
When onions become light golden in color, begin to make roux by adding in the flour mixture slowly while continuing to stir. Stir for 2-3 minutes.
When roux is light golden in color, pour in heavy cream and half & half.
Bring mixture to a boil, then begin stirring in crabmeat.
Bring soup back to a boil.
Ladle soup into bowls.
Pour pumpkin puree in spiral motion starting from the center.
Garnish with extra black pepper and Old Bay seasonings.