Cook chopped bacon in a large skillet over medium heat, stirring often, until crisp, about 6 minutes. Remove from heat; use a slotted spoon to transfer the bacon to a paper towel–lined plate.
Sprinkle chicken tenders with ¼ teaspoon each pepper and salt. Return the skillet to medium heat. Cook the chicken, flipping occasionally, until browned and an instant-read thermometer inserted into the thickest portion registers 165°F, 4 to 6 minutes per side. Transfer to a cutting board; let rest until cool enough to handle, about 5 minutes. Cut or shred into bite-size pieces.
While the chicken cooks, whisk ⅓ cup yogurt, ⅓ cup mayonnaise, 2 tablespoons dill, 1½ tablespoons vinegar, ½ teaspoon garlic powder and the remaining ¼ teaspoon each salt and pepper together in a large bowl. Add chopped broccoli and the cooked bacon and chopped chicken; toss to coat. Add ¾ cup Cheddar and ½ cup scallions; toss to combine.
