Heat olive oil in a saucepan over medium heat. Add chopped shallots and cook gently. Stir often until soft and slightly golden. This builds a strong and flavorful base.

Add minced garlic and fresh thyme to the pan. Stir and cook for one minute. This step releases aroma and adds depth. Do not let garlic burn or turn bitter.

Slowly add red wine into the pan. Stir well and scrape the bottom. This lifts all the tasty bits. Let the mixture simmer and start reducing.

Cook the wine on medium heat for about 10 minutes. It should reduce by half. This step makes the flavor stronger and removes harsh alcohol taste.

Pour in beef stock and mix everything well. Bring to a light boil, then lower the heat. Let it simmer slowly so flavors can blend nicely.

Cook the sauce for 15–20 minutes. Stir sometimes to avoid sticking. The liquid will reduce and thicken slightly. The color will become darker and richer.

Pour the sauce through a strainer into another pan. This removes solids and gives a smooth texture. Press lightly to extract all the liquid.

Add butter into the warm sauce and stir gently. It melts and creates a glossy finish. Taste and adjust salt and pepper before serving.