Cook the bacon in a skillet, or in the oven. Reserve 3 Tbsp of the rendered fat. Let bacon cool slightly before crumbling.
In a large mixing or serving bowl, toss together the spinach mix, pear slices, crumbled blue cheese, chopped walnuts and add the crumbled bacon to the salad once cooled slightly.
Prepare the homemade bacon vinaigrette.In a small skillet or saucepan, add the bacon drippings and whisk in the sugar, spicy brown mustard and vinegar. Add a pinch of both salt and pepper. Once dressing has been well whisked, pour warm over the salad.
Serve Pear & Blue Cheese Salad with Warm Bacon Vinaigrette.