Creamy Crab and Shrimp Seafood Bisque (Rich and Easy)

Ingredients

• 8 oz (225 g) lump crab meat, picked over for shells
• 8 oz (225 g) large shrimp, peeled, deveined, and chopped into bite-size pieces
• 4 tablespoons (56 g) unsalted butter
• 1/2 cup finely diced celery
• 1/3 cup sliced green onions, plus more for garnish
• 2 cloves garlic, minced
• 3 tablespoons all-purpose flour
• 1 tablespoon tomato paste
• 2 cups (480 ml) seafood stock, warmed
• 1 cup (240 ml) whole milk, warmed
• 1 1/2 cups (360 ml) heavy cream, warmed
• 1/4 cup (60 ml) dry sherry, optional
• 1 teaspoon Old Bay seasoning
• 1/2 teaspoon sweet paprika
• 1/4 teaspoon cayenne pepper, optional
• Salt
• black pepper
• 2 tablespoons chopped fresh parsley
• 1 teaspoon fresh lemon juice, plus more to taste