On baking sheet broil bell pepper 3 inches from heat source, turning frequently, until charred on all sides; transfer pepper to brown paper bag and let stand until cool enough to handle, 15 to 20 minutes.
Fit strainer into medium bowl and peel pepper over bowl; remove and discard stem end and seeds, allowing juice from pepper to drip into bowl. Cut pepper into strips and add to bowl with juice; add tomato and cucumber and toss to combine.
In measuring cup or small bowl combine remaining ingredients; mix well. Pour over vegetables in bowl and toss to coat with dressing; cover with plastic wrap and refrigerate for at least 30 minutes. Makes 2 servings.