Rinse broccoli thoroughly and cut into bite size pieces, discarding the stem(s). Dice the red onion. Cook bacon, cool on paper towels, then chop into small pieces. (PRO TIP: Cook bacon in a cold pan. This prevents the bacon from curling, and cooks the fat evenly.)
Place the salad ingredients (broccoli florets, diced red onion, shredded cheddar cheese, sunflower seeds, dried cranberries, and chopped bacon) in a large bowl.
Mix dressing ingredients (mayonnaise, granulated sugar, and red wine vinegar) in a separate bowl, season to taste with salt and pepper. (Use less salt and more pepper because the bacon, cheese, and sunflower seeds all have salt in them.)
Toss ingredients together. Taste and adjust seasoning if needed. Cover and refrigerate a minimum of 1 to 2 hours before serving for best flavor. Keep refrigerated.