Cut cauliflower into 1/2-inch thick slices. Seed and quarter bell pepper. Peel carrots. Brush vegetables lightly with oil.
Grill vegetables over medium-high heat 2 to 4 minutes per side or until grill marks appear. Cool vegetables slightly then cut into bite-size pieces. Place in large glass bowl. Set aside.
Place remaining ingredients in small saucepan. Bring to simmer on medium heat, stirring to dissolve sugar and salt. Reduce heat to low; simmer 5 minutes. Pour hot liquid over vegetables.
Refrigerate 2 hours or until cooled. Serve. Or, cover and refrigerate until ready to serve.