Preheat the oven to 375°F. Cut the carrots into coins
In a large oven-proof skillet, heat the butter and oil. Add the carrots, salt, and pepper and cook over medium-high heat for 5-7 minutes, stirring occaisionally.
When carrots are starting to brown and soften, remove from heat. Add the syrup and vinegar and toss to coat.
Roast in the oven for 10-12 minutes, until carrots are cooked through but not mushy.