In a small bowl pour boiling water over tomato pieces to cover; let stand for 2 minutes. Drain.
For dressing, in a screw-top jar combine tomato pieces, vinegar, the olive oil, basil, mustard, the 2 cloves garlic, sugar, and pepper. Cover and shake well. If desired, cover and chill for up to 24 hours.
Thaw shrimp, if frozen. In a large saucepan bring the water and the 1 clove garlic to boiling; add asparagus. Return to boiling. Simmer, uncovered, for 4 minutes. Add shrimp. Return to boiling. Simmer, uncovered, for 1 to 3 minutes more or until shrimp are opaque. Drain, discarding garlic. Rinse shrimp under cold running water; drain well. Cover and chill for 4 to 24 hours.
To serve, divide greens and pears among 4 salad plates. Top each with some of the shrimp and asparagus. Shake dressing; drizzle each serving with about 2 tablespoons of the dressing. Makes 4 servings.