Combine balsamic vinegar, extra virgin olive oil, Dijon mustard, garlic, salt, black pepper and sugar in a small bowl. Stir with a whisk and set aside. Combine butter or ghee, walnuts and brown sugar in a small frying pan. Sauté until sugar has melted and walnuts are toasted. Cool on a silicone mat or parchment paper and set aside. Rinse the beets and trim the stems of the beets, leaving about 1 inch. (Leave the roots intact.) Fill inner pot with 1 cup water. Place beets in a steamer basket in the inner pot. Cook on 'Manual' mode for 15 minutes. When time is up, do a quick release of pressure and open the Instant Pot. When cool enough to handle, remove steamer basket from inner pot. Cool Instant Pot beets completely. Cut off both ends of each beet. Peel beets with a vegetable peeler or remove skin by hand. Cube beets into 1/2 inch pieces. Start with a layer of arugula. Sprinkle goat cheese and candied walnuts. Add beet pieces. Drizzle with balsamic vinaigrette salad dressing.