Ingredients

• 8 small or 4 large Japanese sweet potatoes
• 4 tablespoons olive oil, divided
• 1/4 cup honey
• 1/4 cup white wine vinegar
• Kosher salt
• Flaky sea salt
• Freshly cracked black pepper

Instructions

1. Prepare a grill for medium-high heat. Rub sweet potatoes with 2 Tbsp. oil and wrap tightly in foil—you can wrap them on their own or put 2 in each packet. Grill, turning every 5 minutes or so, until tender, 30–45 minutes. Unwrap and let cool slightly. (Or, steam in a basket set over a pot filled with 1" of boiling water 30–35 minutes. If not using right away, let cool, then cover and chill until ready to grill—up to 2 days.)
2. Meanwhile, bring honey, vinegar, and a big pinch of kosher salt to a boil in a small saucepan over medium-high (you can do this on the grill if you want), reduce heat, and simmer until just beginning to thicken, about 4 minutes. Keep warm.
3. Cut sweet potatoes in half lengthwise. Rub cut surfaces with 1 Tbsp. oil total; season with kosher salt. Grill, cut side down, without turning, until lightly charred, about 5 minutes. Transfer to a cutting board and brush with honey glaze.
4. Arrange sweet potatoes on a platter and drizzle with more glaze and remaining 1 Tbsp. oil. Season with sea salt and pepper.