Prepare all the ingredients.
Slash the fat side of the magrets in parallel lines.
Add salt and pepper both sides.
Slide in a bit of fresh garlic between fat and meat.
Place them meat to meat and tie them like a roast.
Place them in a baking pan...
...and bake 15 minutes at 250°C.
Halfway, degrease the pan and add a glass of water. Finish the cooking.
When finished, remove the strings from the breasts...
...and slice them finely. The doneness must be rare.