Prep Candied Walnuts: In a medium saucepan over medium heat, add butter, sugar and walnuts. Stir frequently and consistently until sugar is melted and walnuts are fully coated. Keep stirring until walnuts darken in color- you'll want to remove them from heat as soon as they are the perfect color. A few seconds too long and they will burn. This whole process will take less than 5 minutesPour onto parchement paper and using a spatula, break them apart. Let cool.
In the meantime add all dressing ingredients into a bowl and whisk. Set aside.
Place arugula in a large bowl. Season with salt. Toss with dressing and top with walnuts and pears.