1
: In a large saucepan, melt butter over medium heat. Add onions and carrots and cook for 4 to 5 minutes, until softened, stirring often. Stir in flour and cook, stirring, for 2 minutes.
2
: Gradually stir in stock and evaporated milk. Bring to a boil slowly, reduce heat and simmer, uncovered, for 10 minutes, stirring occasionally.
3
: At this stage, soup can be left chunky or puréed. Remove from heat and stir in Cheddar, Parmesan, mustard and Worcestershire sauce and stir until cheese has melted (do not reheat soup or cheese may separate). Season with salt and pepper. Garnish with parsley.