Once you have cut the broccoli, cheese, onion and bacon (if using store bought bacon bits, this step is done for you) into small bite-size pieces, mix them all together with raisins or cranberries in a large bowl.
In a small bowl, whisk together mayonnaise, sugar and vinegar until well combined. If using tomatoes, add to dressing mixture.
Pour dressing over vegetable and cheese mixture and stir together.