Melt 1 tablespoon of the butter in a large nonstick skillet over medium-high heat. Add broccoli, onion and celery. Cook and stir 5 to 6 minutes or until broccoli is crisp-tender. Add another 1 tablespoon of the butter; allow to melt. Stir in parsley, sage, pepper and salt. Add 1/2 cup of the stock; bring to boiling.