Heat oil in a Dutch oven.
Add beef cubes and brown evenly.
Remove beef and set aside.
Sauté onion and garlic until soft.
Add carrots, celery, and potatoes.
Stir for two minutes to combine flavors.
Return beef to the pot.
Pour in broth and red wine.
Add tomato paste, thyme, rosemary, and bay leaves.
Stir well to combine all ingredients.
Cover and simmer for two hours.
Add butternut squash in the last 30 minutes.
Adjust seasoning with salt and pepper.
Mix cornstarch with water if thicker stew desired.
Serve hot and enjoy the hearty flavor.