Step 1

Place racks in upper and lower thirds of oven and set a rimmed baking sheet on each; preheat oven to 375°. Toss sweet potatoes in a large bowl with 2 Tbsp. oil; season with kosher salt and pepper. Carefully spread out half of sweet potatoes in a single layer on each baking sheet. Roast, turning halfway through, until golden brown, 30–35 minutes.

Step 2

Meanwhile, whisk tahini, vinegar, maple syrup, lemon zest, lemon juice, remaining 2 Tbsp. oil, and 2 Tbsp. water in a small bowl; season maple tahini with kosher salt and pepper.

Step 3

Toast pine nuts in a dry medium skillet over medium-high heat, tossing often, until golden brown, about 2 minutes. Transfer to a small bowl and let cool.

Step 4

Spoon some maple tahini into shallow bowls or onto plates and arrange potatoes on top. Scatter dill and pine nuts over and sprinkle with sea salt.