Cook 3 slices chopped thick-cut bacon in a skillet until crisp. Remove with a slotted spoon to paper towels; whisk 2 tablespoons of the drippings with 1 diced small shallot, 1 teaspoon dijon mustard, 3 tablespoons white wine vinegar and 2 tablespoons water. Toss with one 5-ounce bag baby spinach, 1 cup halved red grapes and 1/2 cup pistachios; season with salt and pepper. Top with 1/4 cup crumbled blue cheese and the bacon.