Preheat oven to 400 degrees.
Slice carrots into quarters lengthwise to create long strips.
In a large bowl, whisk together olive oil, honey, thyme, and lemon juice to create a glaze.
Peel the grapefruit and slice into circles (ring shapes) approximately ½ inch thick.
Juice one of the circles into your glaze mixture. Toss carrots in glaze.
Spread carrots in a single layer on a baking pan. Layer the grapefruit circles on top of carrots.
Bake at 400 degrees for 12-18 minutes, until carrots are tender when pierced with a fork.
Remove from the oven and serve as a side.