Melt 1/2 cup butter in a large deep skillet or Dutch oven. Sauté onion and celery 4 to 5 minutes or until crisp-tender. Add chicken broth, crawfish tails, remaining 1/4 cup butter, and red pepper; bring to a boil. Remove from heat. Add cornbread stuffing; gently toss and fluff with a fork until stuffing is moistened.