Step 1

Preheat oven to 400°. Line a rimmed baking sheet with 3 sheets of foil (you’ll need it!). Cut carrots on a diagonal into 3" pieces (halved or quartered lengthwise if large).

Step 2

Spread out carrots on foil. Evenly top with butter, brown sugar, syrup, and red pepper flakes. Season with kosher salt and toss to combine.

Step 3

Bake carrots, tossing every 20 minutes, until tender and browned around the edges, 50–60 minutes. Transfer to a platter (with syrup, if desired). Sprinkle with sea salt (if using).