Cut carrots, first cross-sectioned, then in half. In a small saucepan, heat 1 inch of water to boiling over medium heat. Add carrots and heat to boiling. Cover and simmer until tender, about 15 minutes. Drain and return to saucepan.
Add butter, brown sugar, and lemon juice to carrots; cook over medium heat, stirring gently, until sugar has dissolved and carrots are glazed, about 5 minutes.