Melt butter in a 3-qt. saucepan over medium-high heat; add carrots and next 4 ingredients, and saut 5 to 7 minutes or until tender.
Sprinkle flour over vegetable mixture, and stir until coated. Stir in bouillon cube, milk, and 3 cups water; cook, stirring occasionally, 10 to 11 minutes or until mixture is slightly thickened and bubbly.
Add shredded cheese and red pepper, stirring until well blended.
Serve immediately.
Layer guacamole, tomato slices sprinkled with salt and pepper, bacon slices, and arugula between whole grain bread slices.