Ingredients:

• 3 tablespoons unsalted butter
• 1 small yellow onion, diced (about 1 cup)
• 1/2 stalk celery, diced (about 1/2 cup)
• 1 teaspoon kosher salt, divided, plus more to taste
• 8 ounces white button mushrooms, sliced
• 1/2 teaspoon black pepper, plus more to taste
• 1/4 cup sherry or dry white wine
• 3 tablespoons all-purpose flour
• 1 cup low-sodium chicken broth
• 3/4 cup heavy cream
• 2 cups diced or shredded cooked chicken
• 1 (7-ounce) can pimentos, drained, patted dry, and diced (about 1/2 cup)
• 1/2 cup frozen peas
• 2 to 3 cups cooked white rice, for serving (optional)