Preparation Melt butter in heavy large saucepan over medium heat. Add onion and sauté until translucent, about 12 minutes. Stir in flour. Continue to cook until flour is just golden, stirring constantly, about 4 minutes. Mix in tomatoes, chilies and cream cheese and cook until cheese melts, stirring frequently, about 3 minutes. Simmer until mixture is slightly thickened, about 5 minutes. Add cheddar and stir until melted and mixture bubbles, about 4 minutes. Season with hot pepper sauce. Transfer to chafing dish or fondue pot. Serve with tortilla chips.
Preparation Melt butter in heavy large saucepan over medium heat. Add onion and sauté until translucent, about 12 minutes. Stir in flour. Continue to cook until flour is just golden, stirring constantly, about 4 minutes. Mix in tomatoes, chilies and cream cheese and cook until cheese melts, stirring frequently, about 3 minutes. Simmer until mixture is slightly thickened, about 5 minutes. Add cheddar and stir until melted and mixture bubbles, about 4 minutes. Season with hot pepper sauce. Transfer to chafing dish or fondue pot. Serve with tortilla chips.