The Preparation
Slice onions about 1/2-inch thick, cutting off both ends first.
Melt butter in a large stockpot over medium heat.
Add sliced onions and cook low and slow, stirring occasionally, until deeply caramelized — this takes at least 45 minutes.
Season with garlic powder and salt while the onions cook.
Add roughly chopped garlic to the onions.
Dissolve Better Than Bouillon beef base in 8 cups of boiling water to make broth.
Add broth and Worcestershire sauce to the caramelized onions.
Simmer together for 15-20 minutes; taste and adjust salt.
Ladle soup into oven-safe crocks.
Place toasted baguette slices on top of the soup.
Cover generously with grated Gruyère cheese.
Place under broiler until cheese is melted, bubbly, and golden brown.
Serve immediately.
