• 1 1/2 cup butter
• 4 cups sliced white onions
• 1 3/4 cup flour
• 12 cups beef stock
• 1/2 tsp cayenne pepper
• 1 1/2 tbsp salt
• 1 egg yolk
• 2 tbsp cream

1. In a six-quart soup kettle, melt butter add onions, and reduce heat to very low, cooking until onions are melted down.
2. Be careful not to brown onions in the first stages of cooking.
3. Add flour and cook 5 to 10 minutes more, stirring occasionally.
4. Blend in stock. Reduce heat and simmer about 15 minutes.
5. Remove kettle from heat.
6. Beat together egg yolk and cream, add a little of the soup and mix quickly then add to soup kettle.
7. Serve in Brennans Onion Soup in soup cups with toasted rounds of bread or croutons and sprinkle with grated Parmesan cheese, buttered bread crumbs. Brown under broiler flame and serve.

Recipe makes 3 quarts of Brennan's Onion Soup.