Step 1

Preheat oven to 350º and bring a large pot of salted water to a boil. Toast pine nuts on a rimmed baking sheet, tossing halfway through, until golden brown, 5–7 minutes. Let cool. Leave oven on.

Step 2

Trim root end of leeks (leave as intact as possible so they don’t break apart while cooking) and cook in boiling water until meltingly tender (a paring knife should go all the way through with no resistance), 15–20 minutes. Transfer to paper towels to drain; let cool.

Step 3

While leeks are cooking, cook chiles, orange peel, honey, ¾ cup vinegar, and a pinch of salt in a small saucepan over medium-high heat, stirring often, until reduced by one-third, about 5 minutes.

Step 4

Cut leeks in half lengthwise and transfer to a baking dish; season lightly with salt. Pour warm vinegar mixture over leeks. Bake, uncovered, until sauce is reduced to a glaze and leeks have slightly darkened, 25–30 minutes.

Step 5

Toss parsley, oil, capers, pine nuts, and remaining 1 Tbsp. vinegar in a small bowl; season with salt and pepper. Spoon pine nut salsa over leeks.