First, ensure your beef chuck is cut into 1.5-inch cubes, and dice the onion, chop the celery, and cut the carrots into 1-inch pieces. Mince the garlic and measure out your spices and liquids. Heat 2 tbsp of olive oil in a large, heavy-bottomed pot or Dutch oven over medium-high heat. Season the beef with salt and black pepper, then sear it in batches until well browned on all sides, about 5-10 minutes per batch. This browning step is crucial for developing deep flavor in your stew; don't overcrowd the pot or you'll steam the meat instead of searing it. Remove the seared beef and set aside.

Reduce the heat to medium. Add the diced onion to the same pot, scraping up any browned bits from the bottom, and cook for 3-4 minutes until softened. Stir in the minced garlic and cook for another minute until fragrant. Now, add the 1 cup of dry red wine to deglaze the pot, scraping up all the delicious fond from the bottom. Let the wine simmer until it has reduced by about half, which should take 2-3 minutes. This step adds a wonderful complexity to the stew.

Return the seared beef to the pot. Add the chopped carrots, celery, dried lentils, crushed tomatoes, 6 cups of beef stock, 3 bay leaves, 1 tbsp dried thyme, 1 teaspoon salt, and a pinch of cayenne pepper. Bring the mixture to a boil, then reduce the heat to low, cover the pot, and let it simmer gently for 60-75 minutes, or until the beef is fork-tender and the lentils are cooked through. I always make sure the stew is just barely simmering for tender results; a rapid boil will toughen the meat.

Once the beef is tender, remove the bay leaves from the stew. Stir in the fresh tarragon. Taste the stew and adjust the seasoning with additional salt and black pepper as needed. I find that a final seasoning adjustment is always necessary to bring out the best flavors in any stew. Serve hot and enjoy!