Peel the carrots and cook whole in a saucepan of boiling salted water until firm to the bite; make sure not to overcook and remove just before you think they are done as they will continue cooking once removed from the heat. Drain carrots and cut into 3cm long strips.
In a small bowl combine balsamic vinegar, salt, cayenne, olive oil and oregano. Add garlic and mix well.
Place carrots into a container with a tight fitting lid and pour marinade on top. Cover and marinate in the fridge for 1 day.