Preheat oven to 375°F (190°C). Arrange bacon slices, at least 1 in. (2.5 cm) apart, on parchment paper-lined baking sheet. Brush with maple syrup. Bake 20 to 25 min., or until crisp and golden brown. Cool 5 min. then finely chop; set aside.
Meanwhile, pierce each sweet potato several times with a fork. Microwave, on HIGH, 10 to 12 min, or until fork-tender. Using tongs or oven mitts, transfer to cutting board. Cool 10 min.
Cut each sweet potato in half lengthwise. Scoop flesh into a bowl (leaving a thin wall of flesh inside the intact skins to maintain their shape). Mash the scooped sweet potato until smooth. Stir in ¼ cup (60 mL) goat cheese, thyme, garlic, salt and pepper. Divide mixture evenly into the 4 sweet potato shells. Place on parchment paper-lined baking sheet.
Bake 18 to 20 min., or until heated through. Garnish with reserved bacon, remaining goat cheese and chives.
Substitute feta for goat cheese, and green onions for chives.