Step 1: Sauté the onions and garlic

In a saucepan, melt the butter over medium heat. Add the chopped onion and garlic, and sauté for 5-7 minutes until softened and lightly golden.

Step 2: Add the chestnuts

Stir in the chopped chestnuts and cook for 2-3 minutes to infuse their flavor into the base.

Step 3: Create the roux

Sprinkle the flour over the onion and chestnut mixture. Stir well and cook for 1-2 minutes to eliminate the raw flour taste.

Step 4: Deglaze with red wine

Pour in the red wine, scraping the bottom of the pan to release any browned bits. Simmer for 2-3 minutes until the wine reduces slightly.

Step 5: Add the stock and thyme

Gradually whisk in the stock, ensuring a smooth consistency. Add the thyme sprigs if using, and bring the mixture to a gentle simmer. Cook for 10-15 minutes to allow the flavors to meld.

Step 6: Blend the gravy

For a smooth gravy, blend the mixture using a blender or immersion blender. For a chunkier texture, skip this step.

Step 7: Strain and season

If a silky gravy is preferred, strain the mixture through a fine-mesh sieve. Season with salt and black pepper to taste.

Step 8: Serve

Pour the warm chestnut gravy into a serving jug and serve alongside your favorite roast dishes.