Preheat the oven to 180ºC.

Cut the onion and carrots in big pieces and put them in an ovenproof dish where the breast hardly fits. Spread the bay leaves and cover with the cup of white wine.

In a small pan, melt the butter. Add salt, sugar, pepper, oregano and thyme. Mix well and glaze the whole breast, top and bottom, with this mixture. Place on the bed of vegetables in the baking dish and bake for 50 to 70 minutes, until the breast feels firm to the touch and when inserting a toothpick no juice comes out. The time will depend on the size of the breast.

To make the gravy: Take the breast out of the oven and transfer it to a table. Leave it slightly covered.

In a large pan, heat the chicken broth until it is about to boil. Drip it on the bed of vegetables in the breast's refractory, to melt and gather all the fat that has been left in the pan. Mix lightly with a spoon and return only the liquid to the pan. Discard the onions and carrots.

Bring to a very light boil, and add the tablespoon of butter and the tablespoon of flour. Immediately mix energetically with a balloon to integrate the sauce. Let it boil at a very low heat for 5 minutes. Add red wine and vinegar, season to taste, remove from heat and strain to avoid lumps.