Step 1

Heat oven to 425°F. Line rimmed baking sheet with parchment paper. Using vegetable peeler, remove 4 strips lime zest and squeeze 2 tablespoons juice. Place in small saucepan. Cut white and light green scallion parts into 2-inch pieces, then smash with side of knife (set dark green parts aside). Add to saucepan along with cola, soy sauce, garlic, and ginger.

Step 2

Bring to a boil, then reduce heat and simmer vigorously until slightly thickened and reduced by about half, 25 to 30 minutes. In small bowl, stir together cornstarch and 1 teaspoon cold water until smooth. Stir into cola mixture and boil 3 minutes. Discard solids; transfer 1/2 cup sauce to large bowl and stir in butter to melt. Pour remaining sauce in small bowl and set aside for serving.

Step 3

While sauce is reducing, prick wings all over with tip of paring knife and pat dry. Season with 1/2 teaspoon salt. Transfer wings to prepared pan, spread in single layer and roast until golden brown and just cooked through, 25 minutes.

Step 4

Toss hot cooked wings in cola sauce in large bowl. Return wings to baking sheet, leaving behind any sauce in bowl, and roast until glossy and deep golden brown, 5 to 8 minutes more.

Step 5

Thinly slice dark green parts of scallions and sprinkle over wings; serve with reserved cola sauce for dipping.