Slice The Beets: If you prefer for the beets to be cooked, go ahead and boil or roast them until knife tender. Peel the beets and slice them as thinly as possible with a mandolin or the slicing blade of a food processor.
Make The Vinaigrette: Combine vinegar, oil, sugar, shallot, and Dijon in a jar, add salt and pepper, close and shake until well combined. Dip beet into the dressing and taste, adjust flavoring as desired.
Arrange beets, arugula, and burrata on a platter, drizzle with dressing and serve.