1. Preheat oven to 400°. Toss sweet potato with olive oil and 1 tablespoon vinegar; add sea salt and pepper. Spread in a single layer on a rimmed baking sheet. Place bacon along edges of sheet. Bake at 400° for 12 to 15 minutes or until bacon is crisp. Remove bacon, and drain on a paper towel; let cool, and break into bite-size pieces. Stir sweet potato to coat with bacon drippings, and bake 15 to 20 more minutes or until tender and golden brown around edges.
2. Place spinach in a large bowl; add warm potato, scraping drippings from pan into bowl. Add remaining vinegar and parsley, and gently toss to mix. Add bacon and chèvre, and divide evenly onto plates. Serve warm.