Begin by cutting the beef chuck into bite-sized chunks, then dredge each piece in a mixture of flour, ground cumin, salt, and pepper until well-coated.

In a large pot or Dutch oven, heat vegetable oil over medium-high heat. Add the beef in batches, ensuring not to overcrowd the pot to achieve that perfect golden sear.

Using the same pot with the flavorful drippings, add the chopped onions and sliced mushrooms. Sauté them over medium heat for about 6-8 minutes.

Stir in the minced garlic into the buttery mix of onions and mushrooms, cooking for an additional minute.

Return the seared beef to the pot and pour in the red wine, if using, scraping the bottom to incorporate all those tasty bits.

Bring the mixture to a gentle boil, then reduce the heat to low. Cover and let it simmer for about 2-3 hours.

Once the beef is tender and the stew has thickened to your liking, stir in the sour cream until creamy and well integrated.