Fry bacon in skillet until crisp. Drain on paper towels; crumble. To 1 tablespoon of drippings, add sugar and cornstarch. Add vinegar, water, soy sauce, and pepper. Cook until mixture boils and thickens, stirring constantly. Set aside to let cool slightly. Combine zucchini in a bowl with the crumbled bacon; season with salt then toss with the warm dressing. Arrange on serving plates with sliced tomatoes.
Serves 4 to 6.