Peel the shrimp
Melt the butter in a large, heavy pot (preferably a Dutch oven) over medium heat.
Whisk in the flour and cook, whisking almost constantly until the roux is a light peanut butter color and becomes fragrant, about 8 to 10 minutes.
Add the onions, celery, bell pepper, and garlic and cook, stirring, for another 5 minutes.
Stir in the tomatoes, corn, stock, salt, bay leaves, basil, thyme, pepper, and smoked paprika and bring to a boil.
Reduce the heat to low and simmer for 45 minutes, stirring occasionally.
Stir in the peeled shrimp, parsley, and scallions.
Bring the stew back to a boil over high heat, then turn the heat to low and simmer for 20 minutes.
Remove from the heat, allow the stew to stand for about 15 minutes to really meld the flavors, and adjust seasonings, if desired.