Prepare cheesy dipping sauce. Spread 2 tsp mustard over each tortilla. Top with roast beef, spinach and bell pepper. Roll up tortillas. Serve with sauce.
Cheesy Dipping Sauce: Heat cheese spread and milk in 1 1/2 quart saucepan over medium heat, stirring constantly, until smooth. Stir in onions. Serve warm.
Servings: 6